ifcfg-enp0s3 add a comments to the file code example

Example 1: set static ip centos

IPADDR=192.168.1.200
NETMASK=255.255.255.0
GATEWAY=192.168.1.1
DNS1=1.0.0.1
DNS2=1.1.1.1
DNS3=8.8.4.4

Example 2: set static ip centos

BOOTPROTO=static