ports/158508: Port www/firefox (5.0) results in ~500MB libxul.so

[doppelfish]

With bsd.gecko.mk rev 1.29 in place, the file
/usr/ports/www/firefox/work/mozilla-release/toolkit/library/libxul.so has
a size of 25296KB as reported by "ls -s".  Stripping it doesn't change
its size.  As noted in the original report, stripping the ~500MB lib
brought it to 23328K, so that's probably as good as it gets.

A whopping 18 hits for " -g " remain, all related
to compiling compiling libffi.