Delete useless MSG_TLS_SERVER_PORT

Message MSG_TLS_SERVER_PORT has no purpose since it only used to call
onServerPortReceived (which in turns sends a message to the hander).

This CL directly sends the correct message to the hander.

Bug: NA
Test: manual
Flag: EXEMPT (simplification)
Change-Id: I348df8588ceb90f93c9e48a74f3639fbe9a314a1