There are plenty of systems out there with more than 64 e820
descriptors.  The hard-coded limit is only used during initialization,
so we might as well go nuts.

Print minimal message while loading.

Use the syslinux_memmap data structure for the free memory list.  This
means we get range coalescing; this sometimes generates lists that are
vastly shorter than without range coalescing.

Handle the case of an upward move when there is something in the way.
This happens when loading an SDI image.

ext2/3 directory blocks are *not* ended with inode == 0; that reflects
a deleted block (like 0xe5 in FAT.)  Directory blocks are ended by
directory block exhaustion; the last block is simply made as large as
the whole directory block.

COM32 module to load a Microsoft System Deployment Image (SDI) file.

Class E IPv4 addresses are expected to be reassigned as available for
unicast addresses (probably for site-local use, but that is a major
usage domain of PXE.)