Add BLX driver

* Battery Life eXtender kernel module for msm8974.
* Read more: http://forum.xda-developers.com/nexus-s/development/mod-battery-life-extender-blx-t1257497

Signed-off-by: Cl3Kener <Cl3Kener@gmail.com>
Defconfig: Add BLX

Signed-off-by: Chester Kener <Cl3Kener@gmail.com>
dts: msm8974ac: GPU overclocking to 688MHz