BTS: fix missing GPRS Indicator in SI4 Rest Octets

We do have GPRS Indicator in SI3 Rest Octets, but for some reason
it was absent in SI4 Rest Octets. Let's finally enable it, so we
can extend the existing test cases to check GPRS Indicator in the
Rest Octets of both System Information Type 3 and 4.

Change-Id: Ib55c2673b53b5981e57372f4f8cfb0af32e04132
Signed-off-by: Vadim Yanitskiy <axilirator@gmail.com>
Related: OS#3075
diff --git a/bts/BTS_Tests.ttcn b/bts/BTS_Tests.ttcn
index 3ed3655..4466ad4 100644
--- a/bts/BTS_Tests.ttcn
+++ b/bts/BTS_Tests.ttcn
@@ -241,9 +241,8 @@
 private template (value) SI4RestOctets ts_SI4RestOctets_def
 modifies ts_SI4RestOctets := {
 	gprs_ind := {
-		/* FIXME: GPRS Indicator shall be present here too */
-		presence := CSN1_L,
-		ind := omit
+		presence := CSN1_H,
+		ind := ts_GPRSIndicator_def
 	}
 }