asterisk: Introduce test TC_ims_reregistration

So far Asterisk seems to be doing "initial registration" during
re-registration, instead of using the existing security context.
This is "OK" afaiu, but not the best pick (TS 24.229 5.1.1.4.1).

Related: SYS#6983
Change-Id: Icaeec6e2be3469b9e49d4361ca2b039ab44683c0
diff --git a/asterisk/expected-results.xml b/asterisk/expected-results.xml
index 31a03e5..65a495b 100644
--- a/asterisk/expected-results.xml
+++ b/asterisk/expected-results.xml
@@ -12,6 +12,7 @@
   <testcase classname='Asterisk_Tests' name='TC_ims_registration_timeout_resync_401Unauthorized' time='MASKED'/>
   <testcase classname='Asterisk_Tests' name='TC_ims_registration_timeout_protected_100Trying' time='MASKED'/>
   <testcase classname='Asterisk_Tests' name='TC_ims_registration_timeout_protected_200OK' time='MASKED'/>
+  <testcase classname='Asterisk_Tests' name='TC_ims_reregistration' time='MASKED'/>
   <testcase classname='Asterisk_Tests' name='TC_ims_call_mo' time='MASKED'/>
   <testcase classname='Asterisk_Tests' name='TC_ims_call_mo_noprecondition' time='MASKED'/>
   <testcase classname='Asterisk_Tests' name='TC_ims_call_mt' time='MASKED'/>