cypress: report led status via sysfs

Change-Id: Iddecb0688e758eca3ba77b520510a6728ad1e3bb
cypress-touchkey: remove backlight timeout feature

Userspace implementation:
http://review.cyanogenmod.org/48796
http://review.cyanogenmod.org/48872
http://review.cyanogenmod.org/48884

Change-Id: Id4ac50168220310e82aa4aae367dad4e72e3a9c3

Conflicts:

	drivers/input/touchscreen/mms_ts.c