[show][muxcable] fix show mux hwmode muxdirection RC (#2812)

What I did
show mux hwmode muxdirection always has rc==1.

Fixed the issue below:

get_grpc_cached_version_mux_direction_per_port has reverted TRUE/FALSE return value compared to get_hwmode_mux_direction_port. The former is used to get results for active-active ports, the latter is used to get results for active-standby ports.
Use sys.exit() instead of return rc. CLI rc is different from function return value.
Fixed show mux grpc muxdirection as well.
sign-off: Jing Zhang

How to verify it
Tested on DUTs to verify rc. Run commands for single port and all ports, with and without --json.
Passed all UTs.

show/muxcable.py

@@ -1370,13 +1370,14 @@ def muxdirection(db, port, json_output):
                 headers = ['Port', 'Direction', 'Presence']
             click.echo(tabulate(body, headers=headers))
 
-        return rc
+        rc_exit = EXIT_SUCCESS if rc==0  else EXIT_FAIL
+        sys.exit(rc_exit)
 
     else:
 
         logical_port_list = platform_sfputil_helper.get_logical_list()
 
-        rc_exit = True
+        rc_exit = EXIT_SUCCESS
         body = []
         active_active = False
         if json_output:
@@ -1425,8 +1426,9 @@ def muxdirection(db, port, json_output):
                     active_active = True
                 else:
                     rc = create_active_standby_mux_direction_result(body, port, db)
-                if rc != 0:
-                    rc_exit = False
+
+            if rc != 0:
+                rc_exit = EXIT_FAIL
 
 
 
@@ -1440,8 +1442,7 @@ def muxdirection(db, port, json_output):
                 headers = ['Port', 'Direction', 'Presence']
             click.echo(tabulate(body, headers=headers))
 
-        if rc_exit == False:
-            sys.exit(EXIT_FAIL)
+        sys.exit(rc_exit)
 
 
 @hwmode.command()
@@ -2116,7 +2117,7 @@ def get_grpc_cached_version_mux_direction_per_port(db, port):
     mux_info_dict = {}
     mux_info_full_dict = {}
     trans_info_full_dict = {}
-    mux_info_dict["rc"] = False
+    mux_info_dict["rc"] = 1
 
     # Getting all front asic namespace and correspding config and state DB connector
 
@@ -2158,7 +2159,7 @@ def get_grpc_cached_version_mux_direction_per_port(db, port):
 
     mux_info_dict["presence"] = presence
 
-    mux_info_dict["rc"] = True
+    mux_info_dict["rc"] = 0
 
     return mux_info_dict
 
@@ -2198,14 +2199,15 @@ def muxdirection(db, port, json_output):
             rc = create_active_active_mux_direction_result(body, port, db)
             click.echo(tabulate(body, headers=headers))
 
-        return rc
+        rc_exit = EXIT_SUCCESS if rc==0  else EXIT_FAIL
+        sys.exit(rc_exit)
 
     else:
 
 
         logical_port_list = platform_sfputil_helper.get_logical_list()
 
-        rc_exit = True
+        rc_exit = EXIT_SUCCESS
         body = []
         if json_output:
             result = {}
@@ -2242,8 +2244,8 @@ def muxdirection(db, port, json_output):
             else:
                 rc = create_active_active_mux_direction_result(body, port, db)
 
-            if rc != True:
-                rc_exit = False
+            if rc != 0:
+                rc_exit = EXIT_FAIL
 
         if json_output:
             click.echo("{}".format(json.dumps(result, indent=4)))
@@ -2252,7 +2254,6 @@ def muxdirection(db, port, json_output):
 
             click.echo(tabulate(body, headers=headers))
 
-        if rc_exit == False:
-            sys.exit(EXIT_FAIL)
+        sys.exit(rc_exit)