Gets max channel count from AudioSystem.java

The FCC_LIMIT in the audio.h header might be different from the device
on which the test is running. So instead grabbing the max channel count
from AudioSystem.java, which will get the FCC_LIMIT of the current
device.

Test: Yes, this fixes a cts test
Bug: 334122058
Change-Id: I0900ffb9bd449eea215d1f3cf4a4a7bb9b0e4735
Flag: EXEMPT bugfix
4 files changed