libmsc: set registered_delivery field in SMPP 3.4 DELIVER_SM messages

Propagate the status report request field to the SMPP message through
the registered_delivery field, so the ESME knows that the mobile phone
is asking for explicit delivery acknowledgment is required. See SMPP 3.4
specs section 5.2.17.

Change-Id: I59af60fa89cd10ae973c5e122789e3e03e3728ee
1 file changed