Change name and usage of presym macros

To be also able to build mruby without presym in the future. However,
`MRB_QSYM` has been removed and changed as follows:

### Example

|       Type                | Symbol |  Previous Style  |   New Style    |
|---------------------------|--------|------------------|----------------|
| Operator                  | &      | MRB_QSYM(and)    | MRB_OPSYM(and) |
| Class Variable            | @@foo  | MRB_QSYM(00_foo) | MRB_CVSYM(foo) |
| Instance Variable         | @foo   | MRB_QSYM(0_foo)  | MRB_IVSYM(foo) |
| Method with Bang          | foo!   | MRB_QSYM(foo_b)  | MRB_SYM_B(foo) |
| Method with Question mark | foo?   | MRB_QSYM(foo_p)  | MRB_SYM_Q(foo) |
| Mmethod with Equal        | foo=   | MRB_QSYM(foo_e)  | MRB_SYM_E(foo) |

This change makes it possible to define, for example, `MRB_IVSYM(foo)` as
`mrb_intern_lit(mrb, "@" "foo")`, which is useful if we support building
without presym in the future.

1 files changed, 2 insertions, 2 deletions

diff --git a/mrbgems/mruby-method/src/method.c b/mrbgems/mruby-method/src/method.c
index 0a2897847..7699693fd 100644
--- a/mrbgems/mruby-method/src/method.c
+++ b/mrbgems/mruby-method/src/method.c
@@ -324,10 +324,10 @@ mrb_search_method_owner(mrb_state *mrb, struct RClass *c, mrb_value obj, mrb_sym
     if (unbound) {
       goto name_error;
     }
-    if (!mrb_respond_to(mrb, obj, MRB_QSYM(respond_to_missing_p))) {
+    if (!mrb_respond_to(mrb, obj, MRB_SYM_Q(respond_to_missing))) {
       goto name_error;
     }
-    ret = mrb_funcall_id(mrb, obj, MRB_QSYM(respond_to_missing_p), 2, mrb_symbol_value(name), mrb_true_value());
+    ret = mrb_funcall_id(mrb, obj, MRB_SYM_Q(respond_to_missing), 2, mrb_symbol_value(name), mrb_true_value());
     if (!mrb_test(ret)) {
       goto name_error;
     }