configs: Support 2 instances of "primary input"

No Audio heard in FM Speaker when FM record and FM speaker are on simultaneously

With default values for maxActiveCount and maxOpenCount,
FM app is unable to record and play FM audio on speaker simultaneously
since it uses application loop back(AudioRecord->AudioTrack)
to route FM audio to non-default devices(Speaker)

Add attributes maxActiveCount="2" and maxOpenCount="2" to mixPort "primary input"

CRs-fixed: 2249758
Change-Id: I82a1cb0d5596486d531d5324b91f932f52b07f9e