db: Fix fall-out with the subscriber removal in the subscriber deletion code

The sender_id is gone so the code that attempted to delete SMS
didn't work anymore. Delete the SMS based on src_addr or the
dest_addr.

Fixes:
======================================================================
ERROR: testSubscriberAddRemove (__main__.TestCtrlNITB)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "tests/ctrl_test_runner.py", line 379, in testSubscriberAddRemove
    r = self.do_set('subscriber-delete-v1', '2620345')
  File "tests/ctrl_test_runner.py", line 114, in do_set
    return self.recv_msgs()[id]
KeyError: 1002
1 file changed
tree: 7f7727bfbbef2a269e2efc4b0002c72d94b1da23
  1. debian/
  2. hlrsync/
  3. linux-kernel/
  4. openbsc/
  5. wireshark/
  6. README