Allow minimum brightness

Signed-off-by: Michael Bestas <mikeioannina@gmail.com>

Change-Id: I523390c25f9401371d9517f9e3ba4b4959ba8520
fix DeviceSettings and set brightness & max_brightness
Merge https://github.com/LegacyXperia/android_device_semc_msm7x30-common into jb-4.2