Map power button on reference remote to KEYCODE_TV_POWER

After this change, the power button on the reference remote will function
as a power toggle for the HDMI-connected display (=TV) power state. The
device will then follow the TV power state.

Bug: 157402294
Test: N/A
Change-Id: I462f792f5aae8c47c876d3ea3dfea64fc1c551b5
1 file changed