Fix help handling with different number of devices

[AShivangi]

Problem solved by the commit

Currently, 0 and multiple device help print is treated as the same scenario.

Bug / issue (if any) fixed, which PR introduced the bug, how it was discovered

Internal testing

How problem was solved, alternative solutions (if any) and why they were rejected

0 devices -> print bare minimum help, i.e., no tests and only host report under examine
1 device -> prints help custom for that device
2 devices -> gives a NOTE and prints custom help for one of the devices

This fix is limited to subcommand helps. The next iteration of change will reflect it at xrt-smi level

Risks (if any) associated the changes in the commit

N/A

What has been tested and how, request additional testing if necessary

0 device (win):

xrt-smi examine --help

COMMAND: examine

DESCRIPTION: This command will 'examine' the state of the system/device and will generate a report of interest
               in a text or JSON format.

USAGE: xrt-smi examine [-h] [-d arg] [-f arg] [-o arg] [-r arg]

OPTIONS:
  -d, --device       - The Bus:Device.Function (e.g., 0000:d8:00.0) device of interest
  -f, --format       - Report output format. Valid values are:
                        JSON        - Latest JSON schema
                        JSON-2020.2 - JSON 2020.2 schema
  -h, --help         - Help to use this sub-command
  -o, --output       - Direct the output to the given file
  -r, --report       - The type of report to be produced. Reports currently available are:
                         host - Host information


GLOBAL OPTIONS:
  --verbose          - Turn on verbosity
  --batch            - Enable batch mode (disables escape characters)
  --force            - When possible, force an operation

1 device (win):

xrt-smi examine --help

COMMAND: examine

DESCRIPTION: This command will 'examine' the state of the system/device and will generate a report of interest
               in a text or JSON format.

USAGE: xrt-smi examine [-h] [-d arg] [-f arg] [-o arg] [-r arg]

OPTIONS:
  -d, --device       - The Bus:Device.Function (e.g., 0000:d8:00.0) device of interest
  -f, --format       - Report output format. Valid values are:
                        JSON        - Latest JSON schema
                        JSON-2020.2 - JSON 2020.2 schema
  -h, --help         - Help to use this sub-command
  -o, --output       - Direct the output to the given file
  -r, --report       - The type of report to be produced. Reports currently available are:
                         aie-partitions - AIE partition information
                         host           - Host information
                         platform       - Platforms flashed on the device
                         telemetry      - Telemetry data for the device


GLOBAL OPTIONS:
  --verbose          - Turn on verbosity
  --batch            - Enable batch mode (disables escape characters)
  --force            - When possible, force an operation

2 devices (linux):

xrt-smi examine --help 
NOTE: Multiple devices found. Showing help for 0000:18:00.1 device


COMMAND: examine

DESCRIPTION: This command will 'examine' the state of the system/device and will generate a report of interest
               in a text or JSON format.

USAGE: xrt-smi examine [-h] [-d arg] [-f arg] [-o arg] [-r arg]

OPTIONS:
  -d, --device       - The Bus:Device.Function (e.g., 0000:d8:00.0) device of interest
  -f, --format       - Report output format. Valid values are:
                        JSON        - Latest JSON schema
                        JSON-2020.2 - JSON 2020.2 schema
  -h, --help         - Help to use this sub-command
  -o, --output       - Direct the output to the given file
  -r, --report       - The type of report to be produced. Reports currently available are:
                         aie             - AIE metadata in xclbin
                         aiemem          - AIE memory tile information
                         aieshim         - AIE shim tile status
                         debug-ip-status - Status of Debug IPs present in xclbin loaded on device
                         dynamic-regions - Information about the xclbin and the compute units
                         electrical      - Electrical and power sensors present on the device
                         error           - Asyncronus Error present on the device
                         firewall        - Firewall status
                         mailbox         - Mailbox metrics of the device
                         mechanical      - Mechanical sensors on and surrounding the device
                         memory          - Memory information present on the device
                         pcie-info       - Pcie information of the device
                         qspi-status     - QSPI write protection status
                         thermal         - Thermal sensors present on the device


GLOBAL OPTIONS:
  --verbose          - Turn on verbosity
  --batch            - Enable batch mode (disables escape characters)
  --force            - When possible, force an operation

Documentation impact (if any)

N/A