[xmonad] Building xmonad / X11 fails on Mac OS X 10.11.3 El Capitan.

[Christoph R. Murauer]

> Am 21.02.2016 um 22:06 schrieb Brandon Allbery <allbery.b at gmail.com>:
> 
> pkg-config isn't required, although it can help. If you do use it, you'll need to have PKG_CONFIG_PATH in the environment pointing to the pkgconfig databases (yes, plural; one in lib, one in share) under /opt/X11 or /usr/X11 for it to find the X11 libraries.

You are right. I gave it a second try and, it worked with the 2 commands without pkg-config or other things.

Thanks.