drm/vmwgfx: Tighten the security around buffer maps
drm/vmwgfx: Tighten the security around buffer maps

Make sure only buffer objects that are referenced by the client can be mapped.

Signed-off-by: Thomas Hellstrom <a26490dfbee4be3d38287ad6448444504f58193c@vmware.com>
Reviewed-by: Brian Paul <3cb4e1df5ec4da2c7c4af7c52cec8cf340a55a10@vmware.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs