[CHERRY-PICK] FatPkg/FatPei: Check array offset before use (#245)

## Description

Move the range check before array access to enforce the bounds
as expected.

Cc: Ray Ni <ray.ni@intel.com>
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>
(cherry picked from commit 3ce5f2d)

- [ ] Impacts functionality?
- **Functionality** - Does the change ultimately impact how firmware
functions?
- Examples: Add a new library, publish a new PPI, update an algorithm,
...
- [ ] Impacts security?
- **Security** - Does the change have a direct security impact on an
application,
    flow, or firmware?
  - Examples: Crypto algorithm change, buffer overflow fix, parameter
    validation improvement, ...
- [ ] Breaking change?
- **Breaking change** - Will anyone consuming this change experience a
break
    in build or boot behavior?
- Examples: Add a new library class, move a module to a different repo,
call
    a function in a new library class in a pre-existing module, ...
- [ ] Includes tests?
  - **Tests** - Does the change include any explicit test code?
  - Examples: Unit tests, integration tests, robot tests, ...
- [ ] Includes documentation?
- **Documentation** - Does the change contain explicit documentation
additions
    outside direct code modifications (and comments)?
- Examples: Update readme file, add feature readme file, link to
documentation
    on an a separate Web page, ...

## How This Was Tested

- Run CodeQL before and after the change.

## Integration Instructions

N/A

FatPkg/FatPei/FatLiteApi.c

@@ -464,7 +464,7 @@ GetRecoveryCapsuleInfo (
       // Find corresponding physical block device
       //
       BlockDeviceNo = PrivateData->Volume[Index].BlockDeviceNo;
-      while (PrivateData->BlockDevice[BlockDeviceNo].Logical && BlockDeviceNo < PrivateData->BlockDeviceCount) {
+      while (BlockDeviceNo < PrivateData->BlockDeviceCount && PrivateData->BlockDevice[BlockDeviceNo].Logical) {
         BlockDeviceNo = PrivateData->BlockDevice[BlockDeviceNo].ParentDevNo;
       }