New hearing device pairing page (2/2): MFi devices

Some of the hearing aids support both ASHA + MFi, however, they only
advertise MFi service uuid in advertisement packets.

We can filter the devices with MFi uuid while scanning and then connect
gatt to discover the remote services before pairing to make sure if the
devices are compatible with Android or not. Only devices that support
ASHA/HAP will be shown.

Bug: 307890347
Test: atest HearingDevicePairingFragmentTest
Change-Id: Ie1f4eedddd4c43fad0fcbcd35f436dea5ab06925