bts: move f_pad_oct() to Osmocom_Types as it's generally useful

Change-Id: I4df99e5612c67006eb2998529425956fb4a664af
diff --git a/bts/BTS_Tests.ttcn b/bts/BTS_Tests.ttcn
index 0506e64..5481838 100644
--- a/bts/BTS_Tests.ttcn
+++ b/bts/BTS_Tests.ttcn
@@ -3676,14 +3676,6 @@
 	setverdict(pass);
 }
 
-private function f_pad_oct(octetstring str, integer len, OCT1 pad) return octetstring {
-	var integer strlen := lengthof(str);
-	for (var integer i := 0; i < len-strlen; i := i+1) {
-		str := str & pad;
-	}
-	return str;
-}
-
 /* Send PAGING via RSL, expect it to shw up on PCU socket */
 testcase TC_pcu_paging_from_rsl() runs on test_CT {
 	f_init_pcu_test();
diff --git a/library/Osmocom_Types.ttcn b/library/Osmocom_Types.ttcn
index ffd5df5..046a9ea 100644
--- a/library/Osmocom_Types.ttcn
+++ b/library/Osmocom_Types.ttcn
@@ -162,5 +162,13 @@
 	return ret;
 }
 
+function f_pad_oct(octetstring str, integer len, OCT1 pad) return octetstring {
+	var integer strlen := lengthof(str);
+	for (var integer i := 0; i < len-strlen; i := i+1) {
+		str := str & pad;
+	}
+	return str;
+}
+
 
 } with { encode "RAW"; variant "FIELDORDER(msb)" }