phosphor-software-manager: Create new UBI bbclass

Remove from the base phosphor-software-manager recipe everything
that is conditional in the ubi-fs distro feature and put it
in its own class.
This allows for the base recipe to be cleaner and for future
specific packages to be added conditionally.

Tested: Built witherspoon and romulus and verified only
witherspoon contained the UBI-specific files.
Booted a witherspoon and a romulus qemu.

Change-Id: I2a783abc6152aadcf212a35f0060409f8dac2241
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
diff --git a/meta-phosphor/common/recipes-phosphor/packagegroups/packagegroup-obmc-apps.bb b/meta-phosphor/common/recipes-phosphor/packagegroups/packagegroup-obmc-apps.bb
index 2199e03..56d78d1 100644
--- a/meta-phosphor/common/recipes-phosphor/packagegroups/packagegroup-obmc-apps.bb
+++ b/meta-phosphor/common/recipes-phosphor/packagegroups/packagegroup-obmc-apps.bb
@@ -97,6 +97,7 @@
 
 ${PN}-software-extras_df-obmc-ubi-fs = " \
         phosphor-image-signing \
+        phosphor-software-manager-updater-ubi \
         "
 
 SUMMARY_${PN}-software = "Software applications"