openpower-software-manager: New virtual pnor bbclass

Create a new virtual pnor bbclass to hold the updatesymlinks systemd
service file. This service file was moved because it doesn't depend
on the filesystem layout. Enable it if the virtual-pnor distro feature
is selected.

Tested: Verified the service file was still present on witherspoon
        since the virtual pnor distro feature is part of ubi.

(From meta-openpower rev: 86c282465aa3d601fcc949233049558ee6851d30)

Change-Id: Id2d91e5bbcce93ed6d8c6750a0fa54fcf5a9615b
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/meta-openpower/classes/openpower-software-manager-virtual-pnor.bbclass b/meta-openpower/classes/openpower-software-manager-virtual-pnor.bbclass
new file mode 100644
index 0000000..c83f4aa
--- /dev/null
+++ b/meta-openpower/classes/openpower-software-manager-virtual-pnor.bbclass
@@ -0,0 +1,5 @@
+PACKAGECONFIG_append = " virtual_pnor"
+
+SYSTEMD_SERVICE_${PN} += " \
+        obmc-vpnor-updatesymlinks.service \
+        "