onig: do not use system headers
When build on host with older eglibc (Ubuntu 12.04) build fails with:
/tmp/OE/build/tmp-eglibc/sysroots/genericarmv8/usr/include/bits/predefs.h:23:3: error: #error "Never use <bits/predefs.h> directly; include <stdc-predef.h> instead."
(From meta-openembedded rev:
7d0967c4412a80272825cdf410057d9fd195920d)
Signed-off-by: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>