expressatt: add support for panel color shifting based on a sysfs interface

Also update panel color offset application.

Based on following commits from d2 and apexq:
https://github.com/CyanogenMod/android_kernel_samsung_d2/commit/48ed09fe4187e14c8702ed52ac8e5f323784a41b
https://github.com/CyanogenMod/android_kernel_samsung_d2/commit/90459ce34ecd1c31591feddfea4b3a1d88ca314e
https://github.com/CyanogenMod/android_kernel_samsung_d2/commit/41db8f4436b2c55bf9fe1932136e8cae3b04821f

Change-Id: I491434ed4db79d4aa0b2fb9c9b8d8b248d9de898
Merge "expressatt: add support for panel color shifting based on a sysfs interface" into cm-10.2