This commit fixes two issues on macos:
1. Added a patch to fix 'echo -n' issue with MacOS shell
(backported from upstream)
2. Redefined sys.platform='linux' for target build if build host is
MacOS (otherwise, build script tries to use MacOS logic for
OpenWrt(Linux) target build)
Signed-off-by: Sergey V. Lobanov <sergey@lobanov.in>
Sergey V. Lobanov