meta-openpower: Add phosphor-isolation distro feature

Add phosphor-isolation in meta-openpower, so all openpower machines
enable this feature.

Tested: Build Palmetto with mboxd and verify it boots host successfully.

(From meta-openpower rev: 3f08cb351e0282106ec734a03454a7d8e7bdec62)

Change-Id: I1364305cd1b420e254c3c4728f77b89ed36e25ef
Signed-off-by: Lei YU <mine260309@gmail.com>
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/meta-openpower/conf/distro/openbmc-openpower.conf b/meta-openpower/conf/distro/openbmc-openpower.conf
index 5ee9b7c..96a1366 100644
--- a/meta-openpower/conf/distro/openbmc-openpower.conf
+++ b/meta-openpower/conf/distro/openbmc-openpower.conf
@@ -1,2 +1,3 @@
 require conf/distro/include/phosphor-base.inc
 require conf/distro/include/openpower-distrovars.inc
+require conf/distro/include/phosphor-isolation.inc