Add `locC`, the OFE on locations.

theories/heap_lang/lang.v

@@ -337,6 +337,7 @@ Instance val_inhabited : Inhabited val := populate (LitV LitUnit).
 Instance expr_inhabited : Inhabited expr := populate (Val inhabitant).
 
 Canonical Structure stateC := leibnizC state.
+Canonical Structure locC := leibnizC loc.
 Canonical Structure valC := leibnizC val.
 Canonical Structure exprC := leibnizC expr.