i9300: move libril, use SamsungExynos4RIL class

Change-Id: Idf5a983d659d239ba3324cbd8c9e0be9f4ee3dd3
i9300: Set auto_brightness in sysfs

Write "1" into /sys/class/backlight/panel/auto_brightness when auto-brightness is active, in order to get in kernel one level more of brightness.

Change-Id: I8f104718a6bf8f77f63b6e130a694f75dc0e3554