Add HDMI to Source

HDMI was actually part of InputDevice.java API, and it was later added
into native as part of another CL.
This got left out of the original input.common HAL because the history
of the API was unclear at the time.

Bug: 214604719
Test: none
Change-Id: If9855ed6aea1848b646fe8b34e3f8da29a73b632