FmService: Make usage of audiopatch a build-time option

Change Ib732c8e8328035d2b3e60b7823446d1d75b3c107 assumes all devices
have issues with direct volume configuration and require audiopatching
to be disabled in favor of soft rendering. Don't do that, make it
configurable.

Change-Id: Ia334052043a292d37b44e727769232e55a673d35