ggsn: Configure GTP_CodecPort to decode proper UpdatePDPContextRequest/Response

From GTPC_Types.ttcn:
"""
// determines SUT, needed for decoding updatePDPContextRequest
// and updatePDPContextResponse messages
type enumerated SystemUnderTest{SGSN(0),GGSN(1),CGW(2),MME(3)};
"""

Otherwise decoded UpdatePDPContextResponse is decoded taking choise
UpdatePDPContextResponseSGSN.

Change-Id: I52a27222d0e37ed2170972af3fd0e07da49a8c61
2 files changed