Disable fill cell for gf180/aes-hybrid (+ minor metrics update)

| Metric                                        | Old      | New      | Type     |
| ------                                        | ---      | ---      | ----     |
| placeopt__design__instance__area              |   607255 |   605445 | Tighten  |
| globalroute__antenna_diodes_count             |       41 |       28 | Tighten  |
| detailedroute__route__wirelength              |  1854998 |  1849747 | Tighten  |
| detailedroute__antenna_diodes_count           |       13 |       16 | Failing  |
| finish__timing__setup__ws                     |     -1.4 |    -1.39 | Tighten  |
| finish__timing__drv__hold_violation_count     |      101 |      100 | Tighten  |

Signed-off-by: Matt Liberty <[email protected]>

Author: maliberty

flow/designs/gf180/aes-hybrid/config.mk

@@ -35,6 +35,8 @@ export BALANCE_ROWS = 1
 
 export PDN_TCL = $(PLATFORM_DIR)/openROAD/pdn/pdn_grid_strategy_7t_6M.cfg
 
+export FILL_CELLS=
+
 ifeq ($(USE_FILL),1)
 export DESIGN_TYPE = CELL
 else