patch monado to respect terminate signals

Although it doesn't terminate properly with this it seems to make
`systemctl --user restart monado` work

vr-overlay.nix

@@ -25,7 +25,9 @@
           rev = "2ebbca83e896e0802185277ce0a0a463db7a7892";
           hash = "sha256-JjlKHXd1SD9M8OpgFERZCvAhM0eMxjME96YU38DlKNw=";
         };
-        patches = [];
+        patches = [
+          ./0001-ipc-shutdown-ipc-server-on-SIGTERM.patch
+        ];
       });
     })
   ];