C++: NSDMI fixes

* Do not generate IR for field initializers from uninstantiated templates.
* Add forgotten case to `TranslatedDeclarationEntry`

cpp/ql/lib/semmle/code/cpp/ir/implementation/raw/internal/IRConstruction.qll

@@ -47,6 +47,7 @@ module Raw {
       not var.isFromUninstantiatedTemplate(_) and
       var instanceof StaticInitializedStaticLocalVariable
       or
+      not var.isFromUninstantiatedTemplate(_) and
       var instanceof Field
     ) and
     var.hasInitializer() and

cpp/ql/lib/semmle/code/cpp/ir/implementation/raw/internal/TranslatedDeclarationEntry.qll

@@ -34,6 +34,8 @@ abstract class TranslatedDeclarationEntry extends TranslatedElement, TTranslated
       or
       result = entry.getDeclaration().(GlobalOrNamespaceVariable)
       or
+      result = entry.getDeclaration().(Field)
+      or
       not entry.getDeclaration() instanceof StaticInitializedStaticLocalVariable and
       not entry.getDeclaration() instanceof GlobalOrNamespaceVariable and
       not entry.getDeclaration() instanceof Field and