add: blx
drivers: misc: Add BLX driver for hammerhead

neo:

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

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
blx: fix init charging level