Have freebsd port use pkg info if the freebsd version is >= 10000017

The port package provider for FreeBSD was not checking if the freebsd version is version 10. This causes the provider to attempt to use 'pkg_info' instead of 'pkg info'. This PR should fix this bug.
Mostly to match the functionality in the primary caller, lib/chef/resource/freebsd_package.rb. Can certainly revert it back to makefile_variable_value here.