drm/radeon: Ensure radeon bo is unreserved in radeon_gem_va_ioctl

Found with lockdep while testing gpu reset.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Matthew Dawson <matthew@mjdsystems.ca>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/radeon_gem.c

@@ -663,6 +663,7 @@ int radeon_gem_va_ioctl(struct drm_device *dev, void *data,
 	bo_va = radeon_vm_bo_find(&fpriv->vm, rbo);
 	if (!bo_va) {
 		args->operation = RADEON_VA_RESULT_ERROR;
+		radeon_bo_unreserve(rbo);
 		drm_gem_object_unreference_unlocked(gobj);
 		return -ENOENT;
 	}