drm/amdgpu/debugfs: fix memory leak when pm_runtime_get_sync failed

Fix memory leak in amdgpu_debugfs_gpr_read not freeing data when
pm_runtime_get_sync failed.

Fixes: a9ffe2a9 ("drm/amdgpu/debugfs: properly handle runtime pm")
Signed-off-by: Chen Tao <chentao107@huawei.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -937,7 +937,7 @@ static ssize_t amdgpu_debugfs_gpr_read(struct file *f, char __user *buf,
 
 	r = pm_runtime_get_sync(adev->ddev->dev);
 	if (r < 0)
-		return r;
+		goto err;
 
 	r = amdgpu_virt_enable_access_debugfs(adev);
 	if (r < 0)
@@ -967,7 +967,7 @@ static ssize_t amdgpu_debugfs_gpr_read(struct file *f, char __user *buf,
 		value = data[result >> 2];
 		r = put_user(value, (uint32_t *)buf);
 		if (r) {
-			result = r;
+			amdgpu_virt_disable_access_debugfs(adev);
 			goto err;
 		}
 
@@ -976,10 +976,13 @@ static ssize_t amdgpu_debugfs_gpr_read(struct file *f, char __user *buf,
 		size -= 4;
 	}
 
-err:
 	kfree(data);
 	amdgpu_virt_disable_access_debugfs(adev);
 	return result;
+
+err:
+	kfree(data);
+	return r;
 }
 
 /**