com32: Use z size specifier for printf-ing size_t variable

Use the z size specifier to printf-ing size_t variables to get rid of gcc
warning format ‘%08x’ expects type ‘unsigned int’, but argument 2 has
type ‘long unsigned int’

Author: Martin Str|mberg <ams@ludd.ltu.se>
Signed-off-by: Gene Cumm <gene.cumm@gmail.com>
txt/syslinux.cfg.txt: Fix SYSAPPEND FSUUID

Reflow for proper AsciiDoc formatting.

Signed-off-by: Gene Cumm <gene.cumm@gmail.com>