sccp: Merge SCCPAddress>>#createForSSN: from norbert, create a test

Tests.st

@@ -25,6 +25,15 @@ TestCase subclass: SCCPTests [
         ^ #('OsmoNetwork')
     ]
 
+    testCreateForSSN [
+        | addr |
+        addr := SCCPAddress createForSSN: 'hlr'.
+        self assert: addr subSystemNumber = SCCPAddress ssnHLR.
+        self assert: addr routedOnSSN.
+        self assert: addr globalTitle isNil.
+        self assert: addr pointCode isNil.
+    ]
+
     testPNCCreate [
         | pnc |
 

sccp/SCCPAddress.st

@@ -41,10 +41,7 @@ Object subclass: SCCPAddress [
 
     SCCPAddress class >> createWith: ssn [
         <category: 'creation'>
-        ^ (SCCPAddress new)
-            ssn: ssn;
-            routedOnSSN: true;
-            yourself
+        ^self createWith: ssn pointCode: nil
     ]
 
     SCCPAddress class >> createWith: ssn poi: aPointCode [
@@ -62,6 +59,11 @@ Object subclass: SCCPAddress [
             yourself
     ]
 
+    SCCPAddress class >> createForSSN: aSymbol [
+        <category: 'creation'>
+        ^ self createWith: (self perform: ('ssn', aSymbol asUppercase) asSymbol)
+    ]
+
     SCCPAddress class >> parseFrom: aByteArray [
         | routed_ssn gti_ind gti len ai ssn pointCode dat |
         <category: 'parsing'>