Fix a parse error in checkOutputForDevice

Fix a parse error in checkOutputForDevice

Fix a small parsing error in parsing the supported formats and sample
rates of a stream out with dynamic values for these parameters.  The
channel mask parser was properly skipping the "=" in the setting
string, but formats and sample rates were not (cauing the first
reported format and sample rate to end up being skipped)

Change-Id: Id227a44f6b5fc0c223f2ce74f94ebb6abc5fa77d
Signed-off-by: John Grossman <johngro@google.com>