Relax constraints on valid ImageReader usage flags

The only allowed format - usage pairs are currently:
* PRIVATE with USAGE_GPU_SAMPLED_IMAGE
* PRIVATE with USAGE_VIDEO_ENCODE
* PRIVATE with USAGE_GPU_SAMPLED_IMAGE | USAGE_VIDEO_ENCODE
* Non-PRIVATE with USAGE_CPU_READ_RARELY
* Non-PRIVATE with USAGE_CPU_READ_OFTEN

This commit enable other cases, ie. PRIVATE with
GRALLOC_USAGE_HW_COMPOSER.

Bug: 77148005
Test: Manually tested it.
Change-Id: I414c25bc62d52a3573461df6cec4d88512509ec4