Test getActiveMicrophones API when mic is found on the device.

Before this patch the default microphone was required to have characteristics
although it is not always an attached device, thus its characteristics can not
be known by the HAL. Additionally, the HAL might not know the active
microphone info of a input stream if it has not been started yet.

This patch only tests microphones which characteristics are reported by the HAL
and start the input stream before requesting active microphones.

Bug: 109787938
Test: vts-tradefed run vts --module VtsHalAudioV4_0Target
Change-Id: If55bfc8210d4f9443d34951f717c6772b46dde04
Merged-In: If55bfc8210d4f9443d34951f717c6772b46dde04