MAP_ANON and MAP_ANONYMOUS are identical. Prefer MAP_ANON for BSD since
the file is now a confusing mix of the two.
Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Kyle Evans <kevans@FreeBSD.org>