at MAXPARTITIONS/OLDMAXPARTITIONS in kernel sources, so that it wouldn't
need to be specified separately in MAKEDEV.conf
change platform MAKEDEV.conf to contain only MD targets and nothing else;
simplify the parsing in MAKEDEV.awk accordingly
when filtering the template, leave only the wanted makedisk_p*() routine
in the output
as pointed out by David Laight
also make it mandatory for MACHINE and MACHINE_ARCH to be set in
environment; it would be possible to use use uname -p/-m, but better
to catch possible cross-build mistakes sooner than later
