* aclocal.m4 (ac_cv_func_mmap_dev_zero): Darwin does not
	allow mmap from /dev/zero.  Don't make decisions for the host
	based on presence or absence of /dev/zero on the build machine.
	(ac_cv_func_mmap_anon): Darwin does have working MMAP_ANON.
	(AC_FUNC_MMAP_FILE): Darwin does have mmap of a file.
	* configure: Regenerate.

From-SVN: r59394