libhardware: Add ifdef around allocSize

 * Non-QC devices with prebuilt grallocs hate this.

Change-Id: I57ce7547e99ec0cf40c4f05f3742348dec4e2d9d
Merge remote-tracking branch 'cm/cm-11.0' into HEAD

Conflicts:
	include/hardware/audio.h
	include/hardware/gralloc.h
	include/hardware/hwcomposer_defs.h
	modules/usbaudio/audio_hw.c

Change-Id: I396c7779396fde7677de85a3c85bbe5e4eacef6c