bluedroid: Disable AVRCP 1.5 by default

Change-Id: I9169e19873f8b8be4e3c62af84273e0e24a472ef
(cherry picked from commit 6f641484741b2f3f4eaf0b1b3d5b4fba818d13bd)
Bluetooth: Change Sampling Frequency to 48 kHz

Change Default Sampling Frequency to 48 kHz by default to
match Audio Source.
CRs-fixed: 436686

Conflicts:
	audio_a2dp_hw/Android.mk
	btif/src/btif_media_task.c
	main/Android.mk

Change-Id: I73b6b2fe93df2dcede345e4063383aeab2fa05ae