* config/ltmain.m4sh (func_mode_compile): In order to find out

* config/ltmain.m4sh (func_mode_compile): In order to find out
about forbidden characters in output, check with grep after checking
func_quote_for_eval result.  Also, warn instead of fail.
* config/general.m4sh (func_quote_for_eval, func_quote_for_expand):
Revert SunOS sh bug workaround patch from 2004-12-28 as it
triggers bugs in the Tru64 5.1B shell.
Reported by Albert Chin <libtool@mlists.thewrittenword.com> and
Nicolas Joly <njoly@pasteur.fr>.