meta-openpower: phosphor-webui add distro suffix

For phosphor-webui, add df-openpower distro suffix to avoid
poisoning other machines or distros using this layer.  This is
effectively bringing this recipe up to the state of other openpower
recipes.

(From meta-openpower rev: 2eaf1e056e0d47c307dce8c5932070a9c12844ec)

Change-Id: I1968bd23b8a4bc4a2f7e9a335a690e48d7ce0850
Signed-off-by: Patrick Venture <venture@google.com>
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/meta-openpower/recipes-phosphor/webui/phosphor-webui.bbappend b/meta-openpower/recipes-phosphor/webui/phosphor-webui.bbappend
index ea81894..17dd739 100644
--- a/meta-openpower/recipes-phosphor/webui/phosphor-webui.bbappend
+++ b/meta-openpower/recipes-phosphor/webui/phosphor-webui.bbappend
@@ -1,4 +1,4 @@
-do_install_append () {
+do_install_append_df-openpower () {
 
 # The webui content is served as pre-compressed gzip content. While nginx can
 # handle this via the gzip_static directive (and we use that), the nginx