remove un-driven signal

Author: WilliamZhang20

src/tpu.v

@@ -23,8 +23,7 @@ module tt_um_tpu (
     wire mmu_en; // internal signal
     reg clear; // reset of PEs only
     wire [2:0] mem_addr; // 3-bit address for matrix and element selection
-    reg mem_load_mat;
-
+    
     wire [2:0] mmu_cycle; // compute/output cycle count, minimum 5, maximum ???
 
     wire [7:0] weight0, weight1, weight2, weight3;