buffet: Migrate from system_name to just name.

To follow up with the most recent push.

BUG=None
TEST=manual

Change-Id: I8702ad25cf52b8dd427e83c944e7b59dcb37d553
Reviewed-on: https://chromium-review.googlesource.com/224290
Reviewed-by: Anton Muhin <antonm@chromium.org>
Tested-by: Anton Muhin <antonm@chromium.org>
Commit-Queue: Anton Muhin <antonm@chromium.org>
diff --git a/buffet/device_registration_storage_keys.h b/buffet/device_registration_storage_keys.h
index a6c9239..2888f5e 100644
--- a/buffet/device_registration_storage_keys.h
+++ b/buffet/device_registration_storage_keys.h
@@ -22,7 +22,7 @@
 extern const char kRobotAccount[];
 // Transient keys
 extern const char kDeviceKind[];
-extern const char kSystemName[];
+extern const char kName[];
 extern const char kDisplayName[];
 
 }  // namespace storage_keys