Camera: Add qcom-compatible symbols

CAF-derived libcamera blobs expect the symbols to be named
*CONTINUOUS_AF*, not *CAF* like in HTC's.
Also, the handleShutter calls are used with a second boolean
argument, to specify whether it's the final shutter callback or just
a sound request. Enable these with BOARD_USE_CAF_LIBCAMERA

Change-Id: I3437c579a686ac64248cefbdf26affdfa0ef6909