Option for static linking of proj4 in gdal

When trying to build gdal in a non-/usr/local/ location, unfortunately it cannot find libproj.dylib, and I cannot see any compile-time configuration option that allows one to point to the custom path (unlike for basically everything else, e.g. options like --with-geotiff=).

One compile-time option that gets around this, though, is statically linking proj4 into gdal.  So this is a addition to the gdal formula adding that option.

I'm guessing that ideally one could just give the path to libproj.dylib, but in this one case I don't see anything other than runtime options (PROJSO) allowing for that path to be set.