Update notes for submitted changes

* gralloc: make private_handle_t layout consistent on 32/64-bit
Update notes for submitted changes

* gralloc: dont hardcode 32bpp as RGBX
Update notes for submitted changes

* Fix PAN control callback definition to match what bluedroid is doing.
Update notes for submitted changes

* Audio HALs are 32-bit only
Update notes for submitted changes

* Camera2 Test: fix test criteria for exposure time