Log Message:
Unify all distinfo.${MACHINE_ARCH} distfiles into one distinfo file, so
that lintpkgsrc -or doesn't want to remove all suse100_* distfiles every
time (because it looks only at "distinfo").

To make it easy to maintain these distinfo files, add a "suse100-distinfo"
target (modelled after www/opera's "opera-distinfo" target), to regenerate
the distinfo file for all supported platforms.

Discussed with tonio.