Drop Prebuilt SuperSU, use afterflash script to flash SuperSU from Na…

…melessROM

From cm11mod Rom commit done by burstlam but was unable to amend commit with his name.
https://github.com/CM11MOD/android_vendor_cm/commit/59dd6eec5315f986e649342306e333c051d05f27

Conflicts:
	config/common.mk