sgsn: Proper shutdown of RAN_Adapter components

Otherwise TTCN3 errors sproadically during shutdown:
""""
SCCP_Emulation.ttcn:5661 Receive operation on port SCCP_SP_PORT succeeded, message from SGSN_Test_0-RAN(414)
...
SCCP_Emulation.ttcn:5293 Sent on MTP3_SCCP_PORT to SGSN_Test_0-M3UA(415) @SCCP_Types.ASP_MTP3_TRANSFERreq_sccp
SCCP_Emulation.ttcn:5293 Outgoing message was mapped to @MTP3asp_Types.ASP_MTP3_TRANSFERreq
SCCP_Emulation.ttcn:5293 Dynamic test case error: Sending data on the connection of port MTP3_SCCP_PORT to 415:MTP3_SP_PORT failed. (Broken pipe)
SCCP_Emulation.ttcn:5293 setverdict(error): none -> error
"""

Similar shutdown is already done in f_cleanup() of SCCP_Tests.ttcn.

Related: OS#4176
Change-Id: I471eb851e5d41de5d8d974ec81be27024d7d313a
2 files changed