drm/radeon: check kmalloc() for failures

We can just return -ENOMEM here if the allocation fails.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/r100.c

@@ -2008,6 +2008,8 @@ int r100_cs_parse(struct radeon_cs_parser *p)
 	int r;
 
 	track = kzalloc(sizeof(*track), GFP_KERNEL);
+	if (!track)
+		return -ENOMEM;
 	r100_cs_track_clear(p->rdev, track);
 	p->track = track;
 	do {