CEC: Remove redundant KEYCODE_HOME

To prevent device going to deep sleep we now use
wakelock and this KEYCODE_HOME can be removed.

Bug: None
Test: atest HdmiCecSystemAudioControlTest#cect_GiveSystemAudioModeStatus
Change-Id: I078f78e84f01911387eac635f5cfd531fafe2d1c
1 file changed