CFR: patch to cleanup usage of SRC_BASE in various ports

[Mark Linimon]

On Tue, Nov 30, 2010 at 03:33:27AM -0600, Ade Lovett wrote:
> Seems like there's an awful lot of duplication of:
> 
> SRC_BASE?= /usr/src
> 
> in those port Makefiles.
> 
> What's wrong with adding the above, with a bit of documentation, to
> bsd.port.mk ?

Nothing at all, but this is a fix I'd like to go ahead and get in
ASAP, as it's holding me up from doing what I need to do.

mcl