library/GSM_RR_Types.ttcn: fix BYTEORDER of MCC/MNC in RAI

Change [1] introduced a regression: PCU_Tests_RAW.TC_pcuif_suspend
fails since build #443. I have no idea why the BYTEORDER should be
set to 'first' (and not 'last'), but this is the only way I could
make TITAN's RAW encoder generate a valid MCC/MNC pair again.

[1] I481a40daef3eed4a3daa687ad87c4128a13181b4

Change-Id: I70a5b2eed3788be10d62fa421e3ba7444d66c655
diff --git a/library/GSM_RR_Types.ttcn b/library/GSM_RR_Types.ttcn
index d8bf595..4dc0894 100644
--- a/library/GSM_RR_Types.ttcn
+++ b/library/GSM_RR_Types.ttcn
@@ -194,7 +194,10 @@
 	type record LocationAreaIdentification {
 		BcdMccMnc	mcc_mnc,
 		uint16_t	lac
-	} with { variant "" };
+	} with {
+		/* Otherwise '262F45'H is encoded as '24F262'H */
+		variant (mcc_mnc) "BYTEORDER(first)"
+	};
 
 	/* TS 24.008 10.5.1.4 */
 	type enumerated MobileIdentityType {