Another try to fix TWRP brightness

TWRP cannot read brightness file, because of quotes:

I:Cannot find file "/sys/class/leds/lcd-backlight/brightness"

Twrp already had been added quotes:
https://github.com/omnirom/android_bootable_recovery/blob/android-4.4/minui/Android.mk#L35

Change-Id: If3a0aecc7558a2aae2df4f42974319483f72ed1b