frameworks:base: SystemUI: cleanup a duplicate permission

these permissions are duplicated which i found using a script to check for
duplicate permissions.

submitted to AOSP here: https://android-review.googlesource.com/#/c/104810/

Change-Id: I598ed68836303e3ebc5313342f3ddaee6ccea9b2
Merge pull request #87 from CyanogenMod/cm-11.0

frameworks:base: SystemUI: cleanup a duplicate permission