tuna: cmhw: add support for adaptive backlight

Change-Id: I638d313afbee50484dbe53e35808b0cbe3262cbc
tuna: remove screen timeout overlay

Change-Id: I91fafab5886d7022c24d5d966f521ea11d35ba14
Update AGPS data, fix script to overwrite instead of create a new file.
Update GPS LTO data.

TODO: Clean up the hacky symlinking stuff.