gd/os/log.h: Use liblog to control logging level

liblog provides a __android_log_is_loggable function
using the standard "log.tag.<tagname>" property
to check if a given tag and priority should be printed.

This also aligns the behavior with the new
libbluetooth_log library.

Bug: 290841136
Bug: 305066880
Test: mmm packages/modules/Bluetooth
Flag: Exempt, logging change
Change-Id: I492f44c4c199d19923c3b8a4b235e784ad325ed4