Remove legacy keycodes, part 2 (#18660)

* `KC_SYSREQ` -> `KC_SYRQ`

And one `KC_ALT_ERASE` -> `KC_ERAS`

* `KC_NONUS_BSLASH` -> `KC_NUBS`

* `KC_NUMLOCK` -> `KC_NUM`

* `KC_CLCK` -> `KC_CAPS`

* `KC_SCROLLLOCK` -> `KC_SCRL`

* `KC_LBRACKET` -> `KC_LBRC`

* `KC_RBRACKET` -> `KC_RBRC`

* `KC_CAPSLOCK` -> `KC_CAPS`

keyboards/ymdk/ymd96/keymaps/AnthonyWharton/README.md

@@ -8,7 +8,7 @@ keyboard:
 **Note:** This setup has locking Caps Lock and Num Lock keys, so if you wish
 to use this layout and do not have such keys, you should :
 
- - Change the keys `KC_LCAP` and `KC_LNUM` to `KC_CAPS`  and `KC_NUMLOCK` 
+ - Change the keys `KC_LCAP` and `KC_LNUM` to `KC_CAPS`  and `KC_NUM` 
    respectively.
  - Remove the `LOCKING_SUPPORT_ENABLE` and `LOCKING_RESYNC_ENABLE` lines
    from `config.h`.