Introduce new DISTRO_FEATURE for etcd

Creates new DISTRO_FEATURE "etcd" to support etcd package
and associated C++ v3 client API.

etcd will be utilized by new IBM systems to synchronize data across
multiple BMC's within a single system.

Change-Id: I027261789a87ffa0cfc55f16704b256294e672f5
Signed-off-by: Jayanth Othayoth <ojayanth@in.ibm.com>
diff --git a/meta-phosphor/conf/distro/include/etcd.inc b/meta-phosphor/conf/distro/include/etcd.inc
new file mode 100644
index 0000000..a7eff34
--- /dev/null
+++ b/meta-phosphor/conf/distro/include/etcd.inc
@@ -0,0 +1,2 @@
+DISTRO_FEATURES += "etcd"
+DISTROOVERRIDES .= "df-etcd"