rpcrt4: Handle [out]-only non-conformant strings in stubless servers.

dlls/rpcrt4/ndr_stubless.c

@@ -999,6 +999,18 @@ static DWORD calc_arg_size(MIDL_STUB_MESSAGE *pStubMsg, PFORMAT_STRING pFormat)
         size = ComplexStructSize(pStubMsg, pFormat);
         size *= pStubMsg->MaxCount;
         break;
+    case RPC_FC_C_CSTRING:
+    case RPC_FC_C_WSTRING:
+        if (*pFormat == RPC_FC_C_CSTRING)
+            size = sizeof(CHAR);
+        else
+            size = sizeof(WCHAR);
+        if (pFormat[1] == RPC_FC_STRING_SIZED)
+            ComputeConformance(pStubMsg, NULL, pFormat + 2, 0);
+        else
+            pStubMsg->MaxCount = 0;
+        size *= pStubMsg->MaxCount;
+        break;
     default:
         FIXME("Unhandled type %02x\n", *pFormat);
         /* fallthrough */