Update PS state when radio off or unavailable

When radio off or unavailable, CS state has been reset,
but PS state has not updated, in fact both CS and PS
state should be out of service. So SMS will try to be
sent out when sending sms, the result is "could not send"
rather than sms being queued for sending.
This fix will reset PS state to power off or out of
service when radio off or unavailable accordingly.

Bug: 8265430
Change-Id: I46e962c30021ff1273dcc559579bdedc7f432a64
Telephony: Return 'null' when SubscriberId and Line1Number are unavailable

Return 'null' instead of "" (empty string) when Subscriber Id and
Line1Number are unavailable. This confirms to the definition of the
public API.

Bug: 8284793
Change-Id: Ie6395623cf413d51f6e10316aded71e2eaf5592c