drm/amdgpu: Fix '*fw' from request_firmware() not released in 'amdgpu_ucode_request()'

Fixes the below:
drivers/gpu/drm/amd/amdgpu/amdgpu_ucode.c:1404 amdgpu_ucode_request() warn: '*fw' from request_firmware() not released on lines: 1404.

Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Lijo Lazar <lijo.lazar@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_ucode.c

@@ -1398,9 +1398,13 @@ int amdgpu_ucode_request(struct amdgpu_device *adev, const struct firmware **fw,
 
 	if (err)
 		return -ENODEV;
+
 	err = amdgpu_ucode_validate(*fw);
-	if (err)
+	if (err) {
 		dev_dbg(adev->dev, "\"%s\" failed to validate\n", fw_name);
+		release_firmware(*fw);
+		*fw = NULL;
+	}
 
 	return err;
 }