Make gcc happy and remove a couple of warnings

Remove the callbacks from gsm_network for now. A set of different
callbacks will be back. E.g. when the paging is completed, when the
Q.931 like call handling is there...

Remove var's or move them into #if 0, remove unused stuff that looks
like we do not need it anytime soon or #if 0 them, move stuff around.
diff --git a/src/telnet_parser.l b/src/telnet_parser.l
index 796c5c9..e432719 100644
--- a/src/telnet_parser.l
+++ b/src/telnet_parser.l
@@ -182,3 +182,9 @@
 		conn->imsi = NULL;
 	}
 }
+
+__attribute__((unused)) void telnet_unused(void)
+{
+	yyunput(0, 0, 0);
+	input(0);
+}