Support slot switch API in update_engine_client

Test: adb shell update_engine_client --switch_slot=false
Change-Id: I74198e2ef904869e36e5d6be5a85bbbeadbee89c
diff --git a/payload_consumer/postinstall_runner_action.cc b/payload_consumer/postinstall_runner_action.cc
index 051ccbf..c3b8c6b 100644
--- a/payload_consumer/postinstall_runner_action.cc
+++ b/payload_consumer/postinstall_runner_action.cc
@@ -202,8 +202,8 @@
   }
 
   LOG(INFO) << "Performing postinst (" << partition.postinstall_path << " at "
-            << abs_path << ") installed on device " << partition.target_path
-            << " and mountable device " << mountable_device;
+            << abs_path << ") installed on mountable device "
+            << mountable_device;
 
   // Logs the file format of the postinstall script we are about to run. This
   // will help debug when the postinstall script doesn't match the architecture