aspeed: add sample bblayers and local config

Add a minimal sample local.conf and bblayers.conf to enable easy build
setup:

  TEMPLATECONF=meta=aspeed/conf . oe-init-build-env

Change-Id: Id1088c00a889f40a1f33109c8f36919e61d571b2
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/conf/bblayers.conf.sample b/conf/bblayers.conf.sample
new file mode 100644
index 0000000..e52e6be
--- /dev/null
+++ b/conf/bblayers.conf.sample
@@ -0,0 +1,7 @@
+BBPATH = "${TOPDIR}"
+BBFILES ?= ""
+
+BBLAYERS ?= " \
+  ##OEROOT##/meta \
+  ##OEROOT##/meta-aspeed \
+  "