maint: use help2man configured with --disable-nls
Prompted by the continuous integration build failure at:
http://hydra.nixos.org/build/
6038769
The previously committed 'help2man' requires a Perl module
which does not seem to be installed everywhere - and which
is not needed for our purposes:
Can't locate Locale/gettext.pm in @INC
BEGIN failed--compilation aborted at ./man/help2man line 28.
This module was pulled in automatically by the default configure call.
Use the NLS-disabled version instead.
* man/help2man.in: Use help2man configured with the --disable-nls
option to avoid the dependency to the above Perl module.
* man/help2man.diff: Adapt the line numbers of the hunks in the
coreutils-specific patch for help2man to apply without fuzz.
Reported by Pádraig Brady.