Need of administratively disabling IPv6

[enihcam]

需求应用场景 请描述需求应用的场景和方式。

DNS service where IPv6 is not needed, but currently unable to disable:

Feb 11 10:34:52 smartdns[3032]: create icmp socket failed, Address family not supported by protocol
Feb 11 10:34:52 smartdns[3032]: ping 2001::, id = 1
Feb 11 10:34:52 smartdns[3032]: from          2001::: error is Address family not supported by protocol
Feb 11 10:34:52 smartdns[3032]: ping 2001:: end, id 1
Feb 11 10:34:52 smartdns[3032]: IPV6 is not ready or speed check is disabled, disable IPV6 features

建议的方案 实现上述场景建议的方案。

Need an option to administratively disable IPv6, i.e. no IPv6 icmp either.

设备信息

1. 设备信息（CPU，厂家）

2. 固件信息

[pymumu]

IPV6-related functions should be automatically disabled if the kernel does not support them. So it should just be a logging issue.

Latest code optimize log when the kernel does not support ICMPV6