Remove non portable usage of REG_NOERROR.
BSD (like OS X) variants of regex.h do not declare REG_NOERROR, even GNU
regex(3) does not mention REG_NOERROR, just remove it.
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com> Acked-by: Jeroen Hofstee <jeroen@myspectrum.nl>