allow com.android.cellbroadcastservice grant signature permission

permission BROADCAST_SMS is a signature|telephony protection,
configure com.android.cellbroadcastservice as part of telephony apks
in order to be granted with this permission.

Bug: 135956699
Test: manual test
Change-Id: Id31e3ce6662db254b77178bc2d6ee9ec7532bc8d
(cherry picked from commit 3da1104a)
Merged-in: Id31e3ce6662db254b77178bc2d6ee9ec7532bc8d