am a5dce0c1: am 3d7606aa: SIP: enhance timeout and registration status feedback.

Merge commit 'a5dce0c15ac05724b4595d62d521a481c7e1f86a'

* commit 'a5dce0c15ac05724b4595d62d521a481c7e1f86a':
  SIP: enhance timeout and registration status feedback.