service: add android.hardware.media.c2@1.0-service-v4l2 service

This CL adds android.hardware.media.c2@1.0-service-v4l2 service, used
to create C2Component implementation at this repo.

Bug: 152714603
Test: mmm external/v4l2_codec2

Change-Id: If19084b2c08bd2eb36a991e3933bf0372241a1a5