gralloc: new function to query the gem handle of buffer_handle_t

This function can be used from Mesa instead of having to expose the
whole gralloc_drm_handle_t structure.

Change-Id: I1aa5368b21e588d5d711c1005fff2a5296e143a0
Signed-off-by: Tapani Pälli <tapani.palli@intel.com>
2 files changed