fix: failed to add eip

[ShaPoHun]

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What type of this PR

Examples of user facing changes:

• Bug fixes
  add eip所使用的arping -s遇到arp回多个包，会造成eip创建失败。

Which issue(s)

在我使用的环境中，出现arp代答（arping 一个包发出会出现2个同样的回包），造成了eip创建失败。

this PR fixes:
使用arping -D 参数代替arping -s

[root@hci-dev-mst-1 ~]# arping --help
arping: invalid option -- '-'
Usage: arping [-fqbDUAV] [-c count] [-w timeout] [-I device] [-s source] destination
  -D : duplicate address detection mode
  -s source : source ip address

The -D option specifies duplicate address detection mode (DAD). It returns exit status 0, if DAD succeeded i.e. no replies are received.