simplify the code

modified:   set_bonding.sh

	Signed-off-by: swei <swei@linx-info.com>

install_shell/set_bonding.sh

@@ -25,8 +25,7 @@ IF_CONFIG="/etc/sysconfig/network-devices"
 if [ -f ${IF_CONFIG}/ifcfg-bond0 ];then
     echo "bonding exit.."
 else
-grep "^bonding" /etc/sysconfig/modules &> /dev/null
-if [ $? -eq 0 ];then
+if ! grep -q "^bonding" /etc/sysconfig/modules;then
     echo 'bonding mode=6 max_bonds=1' >> /etc/sysconfig/modules
 fi