Add meta-hxt and meta-stardragon-rep2

Initial a new platfom for ARM system

Change-Id: I7309e4387f806b4c8e45a57bd5474a232734c71a
Signed-off-by: Yuan Yao <yao.yuan@hxt-semitech.com>
diff --git a/conf/machine/include/hxt.inc b/conf/machine/include/hxt.inc
new file mode 100644
index 0000000..976e2d0
--- /dev/null
+++ b/conf/machine/include/hxt.inc
@@ -0,0 +1,3 @@
+require conf/machine/include/arm.inc
+
+VIRTUAL-RUNTIME_skeleton_workbook = "${MACHINE}-config"