Simplify w_mask_in tie-off to 48'b0

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Signed-off-by: Jaehyun Kim <jhkim@precisioninno.com>

Author: jhkim-pii

flow/designs/src/bp_quad/bsg_chip_block.sv2v.v

@@ -241514,7 +241514,7 @@ module bsg_mem_1rw_sync_width_p48_els_p256
     .rd_out(data_o),
     .ce_in(_0_net_),
     .we_in(_1_net_),
-    .w_mask_in({48{1'b0}})
+    .w_mask_in(48'b0)
   );
 
   assign _1_net_ = ~w_i;