patch to bsd.ports.mk to support out-of-tree patches.

[Andrzej Tobola]

On Tue, Mar 24, 2015 at 01:33:15PM +0800, Julian Elischer wrote:
> Hi, I've a need to keep soe changes outside of the ports tree, to 
> allow me to tailor
> our installs. I could use the "EXTRA_PATCHES" setting, but I'd have to 
> outline the
> patches every time and keep track of them one by one.

I am using (from a long time) union-mount of local /usr/local/ports over
ports tree:

  % mount | grep ports
  /ftp/pub/BSD/FreeBSD/GIT/ports on /usr/ports (nullfs, read-only)
  <above>:/usr/local/ports on /usr/ports (unionfs, read-only)

  % grep ports /etc/fstab
  /ftp/pub/ports  /usr/ports      nullfs  noauto,ro               0 0
  /usr/local/ports /usr/ports     unionfs noauto,ro               0 0

Simple and effective.
I am using Makefile.local to add local Makefile extensions


cheers,
-a