New recipe for openpower-inventory-upload

This script uploads the BMC inventory to a partition in PNOR
on POWER systems for inclusion in the host device tree.
diff --git a/common/recipes-phosphor/images/obmc-phosphor-image.bbappend b/common/recipes-phosphor/images/obmc-phosphor-image.bbappend
new file mode 100644
index 0000000..7b8aa6f
--- /dev/null
+++ b/common/recipes-phosphor/images/obmc-phosphor-image.bbappend
@@ -0,0 +1,3 @@
+IMAGE_INSTALL += " \
+        inventory-upload \
+"