Moved serv to own tree

rtl/util/clog2.vh

@@ -0,0 +1,10 @@
+function integer clog2;
+  input integer value;
+  integer i;
+  begin
+    value = value - 1;
+    for (i = 0; value > 0; i = i + 1)
+      value = value >> 1;
+    clog2 = (i < 1) ? 1 : i;
+  end
+endfunction