vim-patch:8.1.0324: off-by-one error in cmdidx check

Problem:    Off-by-one error in cmdidx check. (Coverity)
Solution:   Use ">=" instead of ">".
74c8be2c68

Fix pvs/v557.

src/nvim/ex_docmd.c

@@ -10156,7 +10156,7 @@ static void ex_folddo(exarg_T *eap)
 bool is_loclist_cmd(int cmdidx)
   FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT
 {
-  if (cmdidx < 0 || cmdidx > CMD_SIZE) {
+  if (cmdidx < 0 || cmdidx >= CMD_SIZE) {
     return false;
   }
   return cmdnames[cmdidx].cmd_name[0] == 'l';