set DISABLE_NLS only if CONFIG_BUILD_NLS NOT set.
like DISABLE_IPV6 which depends on CONFIG_IPV6
Signed-off-by: Christian Schoenebeck <christian.schoenebeck@gmail.com>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@44930 3c298f89-4303-0410-b956-a3cf2f4a3e73