FreeBSD: don't use v_cache_min/max

[baughj]

Hello,

I'm working on getting Diaspora running on FreeBSD and have been running into some gem bundler errors building sigar extensions on FreeBSD. I notice that you are maintaining a fork that is used by eye, so I would like to integrate those changes here (as sigar is included in Diaspora's gemfile via bundlingeye).

This is basically integrating the changes by @swills in hyperic#68 , which fixes the issue of installing eye on FreeBSD 11R and greater.

I would really be very grateful if you could merge and then make a new release of eye as needed, then I can hopefully make a PR against Diaspora to bump the gem version.

With this patch I'm able to build the resultant sigar.so without issue.

[kostya]

i pushed kostya-sigar v2.0.1, this should be used by last eye.

[baughj]

Thanks very much! Can confirm it works.