* modules/math (Makefile.am): Split sed scripts around 50 sed commands,
to avoid HP-UX limit of 99 commands, in the near future.
* modules/stdlib (Makefile.am): Likewise.
* modules/unistd (Makefile.am): Likewise.
* modules/wchar (Makefile.am): Likewise.
Reported by Albert Chin <bug-gnulib@mlists.thewrittenword.com>.
Suggestion by Ralf Wildenhues <Ralf.Wildenhues@gmx.de> in
<http://lists.gnu.org/archive/html/bug-gnulib/2010-01/msg00216.html>.