meta-romulus: Enable image signature check

Change-Id: I05a4bb07a08cc6e89df302b2f25531a665118e1d
Signed-off-by: Lei YU <mine260309@gmail.com>
diff --git a/meta-romulus/recipes-phosphor/packagegroups/packagegroup-obmc-apps.bbappend b/meta-romulus/recipes-phosphor/packagegroups/packagegroup-obmc-apps.bbappend
index 96e26b2..ea1a7e3 100644
--- a/meta-romulus/recipes-phosphor/packagegroups/packagegroup-obmc-apps.bbappend
+++ b/meta-romulus/recipes-phosphor/packagegroups/packagegroup-obmc-apps.bbappend
@@ -1,2 +1,2 @@
 RDEPENDS_${PN}-inventory += " openpower-occ-control phosphor-cooling-type id-button"
-RDEPENDS_${PN}-extras += "phosphor-webui"
+RDEPENDS_${PN}-extras += " phosphor-webui phosphor-image-signing"