libmsc: move gsm340_rx_sms_submit() to sms_route_mt_sms()

Move the sms message-type-identifier (mti) handling away from the
routing logic. This patch allows us to reuse the sms_route_mt_sms()
function in a follow up patch for sms reports send through SMPP
DELIVER_SM with esm_class = Delivery Receipt whose Change-Id is
Ic1a9023074bfa938099377980b6aff9b262fab2a.

Change-Id: I3f3d30e0762b91e2099243b0be1a4b67cbb5e9c0
1 file changed