support lib for libcutils<->NDK AIDL handle

The native_handle API is notoriously tricky to work with, and this is
expected to be very common. So, adding a small helper library.

Fixes: 175432703
Test: atest libaidlcommonsupport_test
Change-Id: I4a00d2b14fefe6c979ee656e353e117661a1a483