apps/app_dial: Fix crash on non-connect call paths for Privacy/Screening option

In any scenario in which the callee is not connected to the caller, the
current code in app_dial will crash due to raising a Dial End Stasis
Message after the callee channel has been hung up. This patch corrects
the error by simply moving the explicit hangup of the callee (peer)
channel until after the dial end message.

ASTERISK-25691 #close

Change-Id: I816a414014424d0d8c80e2a3cbef13ef8c63798d