audio policy: fix channel match rule for input profiles

Modify channel mask match rule for input profiles in order to
favor profiles with positional masks and less than 2 channels.
This reflects the audio HAL convention to not list index channel
masks for less than 2 channels.

Bug: 131943885
Test: repro steps in bug.
Change-Id: I85e06f3afc2833b6aa7d52675bfd1ffda524fbcf