sysutils/nsysctl: Update to 1.2

• The sysctlinfo interface (sysutils/sysctlinfo-kmod) is now required as build/run dependency which relies on the "oid_label" constant that was introduced in FreeBSD 1200019.
  
  Thus set the port to IGNORE if the above doesn't apply while I'm here. [1]

Changelog:

• Add sysctlinfo kmod support [1]

PR: 240575
Submitted by: Alfonso S. Siciliano <alfix86@gmail.com> (maintainer)