do_3a should only be used if supported by the camera

Some cameras do not supprt 3a. Under those circumstances the call to
do_3a and the subsequent printout of the received values should be
skipped. The actual test can be run without them.

Bug: 33481457
Change-Id: Icb3ff8d77af2dfb06698be53cce5e8667b3acdd2
1 file changed