uninative-tarball: Use xz compression and SDK_ARCHIVE_CMD

Switch uninative to use xz compression instead of bzip2. We can then directly
use the SDK_ARCHIVE_CMD.

(From OE-Core rev: c2e30917542297c0dbef2868d4aeebc05b13ef8b)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/meta/uninative-tarball.bb

@@ -65,5 +65,5 @@ fakeroot archive_sdk() {
 	rm sysroots -rf
 	patchelf --set-interpreter ${@''.join('a' for n in range(1024))} $DEST/usr/bin/patchelf
 	mv $DEST/usr/bin/patchelf $DEST/usr/bin/patchelf-uninative
-	tar ${SDKTAROPTS} -c -j --file=${SDKDEPLOYDIR}/${TOOLCHAIN_OUTPUTNAME}.tar.bz2 .
+	${SDK_ARCHIVE_CMD}
 }