SWDEV-1 - Fix build errors occurred due to -Wunused-variable, -Wunused-but-set-variable, -Wunused-result

- Remove unused variables
- Validate return value of HIP APIs
- Disable failed tests in PSDB
- Use HIP_CHECK_ERROR instead of ASSERT_EQUAL

Change-Id: I9dd0792ecd8c79760b6c948388a953ac8c97b5c2


[ROCm/hip-tests commit: 632802aef8]

projects/hip-tests/catch/hipTestMain/config/config_nvidia_linux.json

@@ -51,6 +51,7 @@
         "Grid_Group_Getters_Positive_Basic",
         "Grid_Group_Getters_Via_Non_Member_Functions_Positive_Basic",
         "Grid_Group_Sync_Positive_Basic",
-        "dynamic_loading_device_kernels_from_library"
+        "dynamic_loading_device_kernels_from_library",
+        "Unit_tiled_partition"
     ]
 }