anv/android: fix images created with external format support

This fixes a case where user first creates image and then later binds it
with memory created from AHW buffer.

Cc: <mesa-stable@lists.freedesktop.org>
Signed-off-by: Tapani Pälli <tapani.palli@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
(cherry picked from commit e4a826b2)