drm/amdgpu/fence: fix ref count leak when pm_runtime_get_sync fails

The call to pm_runtime_get_sync increments the counter even in case of
failure, leading to incorrect ref count.
In case of failure, decrement the ref count before returning.

Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Acked-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -755,8 +755,10 @@ static int amdgpu_debugfs_gpu_recover(struct seq_file *m, void *data)
 	int r;
 
 	r = pm_runtime_get_sync(dev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(dev->dev);
 		return 0;
+	}
 
 	seq_printf(m, "gpu recover\n");
 	amdgpu_device_gpu_recover(adev, NULL);