[SWDEV-540665] Fix power_caps in help text (#642)

Signed-off-by: adapryor <Adam.pryor@amd.com>

amdsmi_cli/amdsmi_helpers.py

@@ -821,8 +821,14 @@ class AMDSMIHelpers():
                     power_cap_min = power_cap_info['min_power_cap']
             except amdsmi_interface.AmdSmiLibraryException as e:
                 logging.debug(f"AMDSMIHelpers.get_power_caps - Unable to get power cap info for device {dev}: {str(e)}")
-                power_cap_min, power_cap_max = "N/A", "N/A"
                 continue
+        
+        # If we never found a real min or max, set them to N/A
+        if power_cap_min == amdsmi_interface.MaxUIntegerTypes.UINT64_T:
+            power_cap_min = "N/A"
+        if power_cap_max == 0:
+            power_cap_max = "N/A"
+
         return (power_cap_min, power_cap_max)