drm/gem: Consider GEM object reclaimable if shrinking fails

drm/gem: Consider GEM object reclaimable if shrinking fails

If the object wasn't moved to a different LRU after the shrink callback
returns, it means the buffer is still reclaimable. Update the remaining
counter to reflect that.

v2:
- Collect R-b

v3:
- Collect R-b

v4:
- No changes

v5:
- No changes

v6:
- No changes

v7:
- No changes

Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patch.msgid.link/20260401134854.2275433-2-boris.brezillon@collabora.com
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>