dselect: Use max() to compute total_width

dselect/baselist.cc

@@ -243,9 +243,7 @@ baselist::baselist(keybindings *kb) {
   nitems= 0;
 
   gap_width = 1;
-  total_width = TOTAL_LIST_WIDTH;
-  if (total_width < COLS)
-    total_width = COLS;
+  total_width = max(TOTAL_LIST_WIDTH, COLS);
 
   xmax= -1;
   list_height=0; info_height=0;