backuptool: Correct supported partitions for addon.d v3

* The plan was to support odm & oem too, but it turned out
  unnecessarily complicated due to their symlink setup,
  while being most likely unused.
  The partitions were removed from the list of supported ones
  in a-only backuptool, but were forgotten in ab backuptool.

Change-Id: I58a01cdc3f5c4239048b204f3313f4bf697dd60a

prebuilt/common/bin/backuptool_ab.sh

@@ -10,7 +10,7 @@ export V=18.1
 export ADDOND_VERSION=3
 
 # Partitions to mount for backup/restore in V3
-export all_V3_partitions="vendor product system_ext odm oem"
+export all_V3_partitions="vendor product system_ext"
 
 # Scripts in /system/addon.d expect to find backuptool.functions in /tmp
 mkdir -p /postinstall/tmp/