drm/amdgpu: potential uninitialized variable in amdgpu_vce_ring_parse_cs()

We shifted some code around in commit 9cca0b8e ("drm/amdgpu: move
amdgpu_cs_sysvm_access_required into find_mapping") and now my static
checker complains that "r" might not be initialized at the end of the
function.  I've reviewed the code, and that seems possible, but it's
also possible I may have missed something.
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

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

@@ -648,7 +648,7 @@ int amdgpu_vce_ring_parse_cs(struct amdgpu_cs_parser *p, uint32_t ib_idx)
 	uint32_t allocated = 0;
 	uint32_t tmp, handle = 0;
 	uint32_t *size = &tmp;
-	int i, r, idx = 0;
+	int i, r = 0, idx = 0;
 
 	p->job->vm = NULL;
 	ib->gpu_addr = amdgpu_sa_bo_gpu_addr(ib->sa_bo);