Do not specify rollback_index_location argument in vbmeta image generation

To match the behavior in make. The module property
rollback_index_location is still needed as it is used to generate
chain_partition arguments.

Test: verify that rollback_index_location argument is never set in make vbmeta partitions
Test: diff soong vs make vbmeta_system partitions
Bug: 390204058
Change-Id: I434388a5a292086746dac58e41d034cdbcdb42a3
diff --git a/filesystem/vbmeta.go b/filesystem/vbmeta.go
index 5f51d34..bbd0edc 100644
--- a/filesystem/vbmeta.go
+++ b/filesystem/vbmeta.go
@@ -181,7 +181,6 @@
 		ctx.PropertyErrorf("rollback_index_location", "must be 0, 1, 2, ...")
 		return
 	}
-	cmd.FlagWithArg("--rollback_index_location ", strconv.Itoa(ril))
 
 	for _, avb_prop := range v.properties.Avb_properties {
 		key := proptools.String(avb_prop.Key)