[syslinux] Update wiki for WDSLINUX installation

[Matt Schulte]

I have just run through the installation of PXELINUX on a WDS and I
noticed that the WDSLINUX wiki is missing a couple of files that must
be copied over to the boot directory of the WDS before it will work:

ldlinux.c32
libcom32.c32
libutil.c32

I am not a member of this list.  I signed up to edit the wiki but the
topic is locked.

Thanks,
Matt