configs: Add voip_tx profile to policy conf

Skype+camcorder concurrency usecase makes Skype
to mute since both uses same record_24 profle, due to
which second audio record request de-prioritizes first
setting isTopOrLatestActive(=true)

Add voip_tx profile making skype to use fasttrack rather
than using record_24 profile

Change-Id: I4a6cee00787f8f587b088d4586e8d13d824144c3