sgsn: test umts aka with gsm sres response

Add ability to test UMTS AKA, by f_gmm_attach() with flags to select UMTS AKA
and to respond to it with GSM AKA SRES.

Add TC_attach_umts_aka_umts_res and TC_attach_umts_aka_gsm_sres.

Change existing TC_attach_* to also call f_gmm_attach(). (Actually,
f_gmm_attach() is almost exactly the previous TC_attach function body.)

osmo-sgsn change I36807bad3bc55c0030d4f09cb2c369714f24bec7 will implement
proper handling of GSM AKA response and make TC_attach_umts_aka_gsm_sres pass.

Related: OS#3193 OS#3224
Change-Id: I201ffeaee4439a413ab8289aceeccca9aba40a7a
diff --git a/sgsn/expected-results.xml b/sgsn/expected-results.xml
index 49ab60c..688e35e 100644
--- a/sgsn/expected-results.xml
+++ b/sgsn/expected-results.xml
@@ -2,6 +2,13 @@
 <testsuite name='Titan' tests='22' failures='5' errors='2' skipped='0' inconc='0' time='MASKED'>
   <testcase classname='SGSN_Tests' name='TC_attach' time='MASKED'/>
   <testcase classname='SGSN_Tests' name='TC_attach_mnc3' time='MASKED'/>
+  <testcase classname='SGSN_Tests' name='TC_attach_umts_aka_umts_res' time='MASKED'/>
+  <testcase classname='SGSN_Tests' name='TC_attach_umts_aka_gsm_sres' time='MASKED'>
+    <failure type='fail-verdict'>Tguard timeout
+      SGSN_Tests.ttcn:MASKED SGSN_Tests control part
+      SGSN_Tests.ttcn:MASKED TC_attach_umts_aka_gsm_sres testcase
+    </failure>
+  </testcase>
   <testcase classname='SGSN_Tests' name='TC_attach_auth_id_timeout' time='MASKED'/>
   <testcase classname='SGSN_Tests' name='TC_attach_auth_sai_timeout' time='MASKED'>
     <failure type='fail-verdict'>Tguard timeout