m7-common: add LPA USB Proxy use case

Change-Id: I979d6ca58ace85bc30a05553705ddae25caadb72
m7-common: enable option to set button brightness

Change-Id: I2aab2fec2a5fa8f6907242498c23029d77b2f81c
Merge "m7: send phone apps status to proximity sensor" into cm-10.2