drivers/amd/pm: check the return value of amdgpu_bo_kmap

amdgpu_bo_kmap() returns error when fails to map buffer object. Add the
error check and propagate the error.
Reviewed-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Li Zhong <floridsleeves@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/pm/powerplay/amd_powerplay.c

@@ -1485,6 +1485,7 @@ static int pp_get_prv_buffer_details(void *handle, void **addr, size_t *size)
 {
 	struct pp_hwmgr *hwmgr = handle;
 	struct amdgpu_device *adev = hwmgr->adev;
+	int err;
 
 	if (!addr || !size)
 		return -EINVAL;
@@ -1492,7 +1493,9 @@ static int pp_get_prv_buffer_details(void *handle, void **addr, size_t *size)
 	*addr = NULL;
 	*size = 0;
 	if (adev->pm.smu_prv_buffer) {
-		amdgpu_bo_kmap(adev->pm.smu_prv_buffer, addr);
+		err = amdgpu_bo_kmap(adev->pm.smu_prv_buffer, addr);
+		if (err)
+			return err;
 		*size = adev->pm.smu_prv_buffer_size;
 	}