net/netip: add a fuzz test
This is a pretty straight port of the fuzz test at https://github.com/inetaf/netaddr.
The MarshalText methods of netip.Addr and net.IP, the Is* methods of netip.Addr
and net.IP and the MarshalText and String methods of netip.Addr are also
checked to ensure that they behave the same way.
Fixes #49367
Change-Id: I44abb01f2a7af45f39597992a1fc7ff0305728fa
GitHub-Last-Rev:
c2323b0ae119b804a58b810ad7f0e2bb1b3a38ac
GitHub-Pull-Request: golang/go#50108
Reviewed-on: https://go-review.googlesource.com/c/go/+/371055
Trust: Matt Layher <mdlayher@gmail.com>
Trust: Katie Hockman <katie@golang.org>
Reviewed-by: Katie Hockman <katie@golang.org>