ttcn3-{sgsn,ggsn}-test: set OSMO_SUT_{HOST,PORT}
This enables the test suite to obtain talloc reports between the
test case executions, which get stored together with the PCAP files.
Change-Id: I61fef7763e6445c231ff2664036e243a9ac96ff6
Related: Icd4c2d80db934535d499598282ed9416d8088163
