remove dsp usage

rtl/ip/mlkem/ntt/barrett_mul_pipe.v

@@ -4,6 +4,7 @@
 // timing-critical NTT paths; the legacy barrett_mul remains combinational for
 // older users.
 
+(* use_dsp = "no" *)
 module barrett_mul_pipe (
     input         clk,
     input         rst_n,
@@ -16,16 +17,16 @@ module barrett_mul_pipe (
     localparam [24:0] Q25 = 25'd3329;
     localparam [12:0] K13 = 13'd5039;
 
-    reg [23:0] p_s1;
+    (* use_dsp = "no" *) reg [23:0] p_s1;
 
     reg [23:0] p_s2;
-    reg [36:0] tk_s2;
+    (* use_dsp = "no" *) reg [36:0] tk_s2;
 
     reg [23:0] p_s3;
     reg [12:0] q_s3;
 
     reg [24:0] p_s4;
-    reg [24:0] qprod_s4;
+    (* use_dsp = "no" *) reg [24:0] qprod_s4;
 
     reg [24:0] r0_s5;
     reg [24:0] r1_s6;