grml-router: fix usage of iptables by dropping full path usage

check4progs expects a program with its full path, otherwise
it fails with:

| /sbin/iptables: binary not found

Thanks: Ralf Moll for the bugreport

diff --git a/sbin/grml-router b/sbin/grml-router
index cd1e19d..52d82c3 100755 (executable)
--- a/sbin/grml-router
+++ b/sbin/grml-router
@@ -21,7 +21,7 @@ fi
 
 # defaults if unconfigured
 [ -n "$OUTDEV" ]   || OUTDEV=auto
-[ -n "$IPTABLES" ] || IPTABLES=/sbin/iptables
+[ -n "$IPTABLES" ] || IPTABLES=iptables
 
 case "$OUTDEV" in
   auto|default)