Move setting the priority U-Boot variable to ubi

The service that sets the priority value is unique to the ubi
layout because there is only one version at a time on the
static layout.
Move the calling of the service to the ubi implementation.

Tested:
- Witherspoon: Priorities are still set.
- Romulus: The BMC.Updater app does not core dump with the
latest sdbusplus changes due to calling a non-existent service.

Change-Id: Ica1c68f00d5cb43c51ee09c5a3851613edf941d5
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
diff --git a/static/item_updater_helper.cpp b/static/item_updater_helper.cpp
index 5cd8b9e..e639e63 100644
--- a/static/item_updater_helper.cpp
+++ b/static/item_updater_helper.cpp
@@ -7,6 +7,11 @@
 namespace updater
 {
 
+void Helper::setEntry(const std::string& entryId, uint8_t value)
+{
+    // Empty
+}
+
 void Helper::clearEntry(const std::string& entryId)
 {
     // Empty