makefile: fix one more do-floorplan gaffe

Signed-off-by: Øyvind Harboe <[email protected]>

Author: oharboe

flow/Makefile

@@ -667,7 +667,7 @@ $(RESULTS_DIR)/2_floorplan.sdc: $(RESULTS_DIR)/2_1_floorplan.odb
 
 .PHONY: do-floorplan
 do-floorplan:
-	$(UNSET_AND_MAKE) do-2_1_floorplan do-2_2_floorplan_io do-2_3_floorplan_macro do-2_4_floorplan_tapcell do-2_5_floorplan_pdn do-2_floorplan
+	$(UNSET_AND_MAKE) do-2_1_floorplan do-2_2_floorplan_io do-2_3_floorplan_macro do-2_4_floorplan_tapcell do-2_5_floorplan_pdn do-2_floorplan do-2_floorplan.sdc
 
 .PHONY: clean_floorplan
 clean_floorplan: