library: clarify length restrictions for SI4 Rest Octets

Change-Id: I54bfe5710f744cdd61752f3e46b1b00e9f2f3e43
Signed-off-by: Vadim Yanitskiy <axilirator@gmail.com>
diff --git a/library/GSM_SystemInformation.ttcn b/library/GSM_SystemInformation.ttcn
index 4cabd77..07ca8e6 100644
--- a/library/GSM_SystemInformation.ttcn
+++ b/library/GSM_SystemInformation.ttcn
@@ -179,7 +179,7 @@
 		RachControlParameters		rach_control,
 		ChannelDescriptionTV		cbch_chan_desc optional,
 		MobileAllocationT		cbch_mobile_alloc optional,
-		RestOctets			rest_octets
+		RestOctets			rest_octets /* 0 .. 10 octets (see 10.5.2.35) */
 	} with { variant "TAG(cbch_chan_desc, iei = '64'O; cbch_mobile_alloc, iei = '72'O)" };
 
 	/* 44.018 9.1.37 */