snapuserd_daemon: Modify incorrect print information

StartServerForUserspaceSnapshots function, if the child resulting from
the separation parameter number is not equal to 4, will be print
Malformed message: expected four sub-arguments, but at present there is
print three

Change-Id: Idc240714a65bc3eeb1e2b9958354de98ca4b329e
diff --git a/fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.cpp b/fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.cpp
index 0557214..36dad33 100644
--- a/fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.cpp
@@ -110,7 +110,7 @@
     for (int i = arg_start; i < argc; i++) {
         auto parts = android::base::Split(argv[i], ",");
         if (parts.size() != 4) {
-            LOG(ERROR) << "Malformed message, expected three sub-arguments.";
+            LOG(ERROR) << "Malformed message, expected four sub-arguments.";
             return false;
         }
         auto handler = user_server_.AddHandler(parts[0], parts[1], parts[2], parts[3]);