upg fix

Change-Id: I1a4fd4f4f229b202d4cf0558d5313332cebb886d
diff --git a/ceph-backend-migration.groovy b/ceph-backend-migration.groovy
index 8b8d256..634cdf8 100644
--- a/ceph-backend-migration.groovy
+++ b/ceph-backend-migration.groovy
@@ -155,7 +155,7 @@
 
                             if (partition?.trim()) {
                                 // dev = /dev/sdi
-                                def dev = partition.replaceAll("[0-9]", "")
+                                def dev = partition.replaceAll('\\d+$', "")
                                 // part_id = 2
                                 def part_id = partition.substring(partition.lastIndexOf("/")+1).replaceAll("[^0-9]", "")
                                 runCephCommand(pepperEnv, HOST, "parted ${dev} rm ${part_id}")