Removing setprop permissions from rild.

There were some auditallow rules left around in rild.te that had logs
showing nothing was triggering them. Thus the rules they were auditing
could be removed, as that's clear indication there's no use for them.
Having rules around that aren't being used does nothing except increase
attack surface and bloat sepolicy, and so should always be removed if
possible.

Test: The device boots
Change-Id: I906ffc493807fbae90593548d478643cda4864eb