Create directory in overlay when building ISO.
Create directory in overlay when building ISO.

Git doesn't track empty directories, so there is no
configs/install-iso/overlay/pacman.d/ directory when one clones the
archiso project.  This causes "make <IMAGENAME>" to fail when
wget tries to fetch the mirrorlist.  The fix is to make the directory
just before calling wget.

Signed-off-by: Aaron Griffin <2851cfca19e1ca9596fe7f146f11c69a7d81b341@gmail.com>

dock0/dock0