Remove useless "ifdef KEYBOARD_*" (#20078)

Co-authored-by: Nick Brassel <nick@tzarc.org>

keyboards/hadron/hadron.c

@@ -1,2 +0,0 @@
-#include "hadron.h"
-

keyboards/hadron/hadron.h

@@ -2,14 +2,6 @@
 
 #include "quantum.h"
 
-#if defined(KEYBOARD_hadron_ver0)
-#    include "ver0.h"
-#elif defined(KEYBOARD_hadron_ver2)
-#    include "ver2.h"
-#elif defined(KEYBOARD_hadron_ver3)
-#    include "ver3.h"
-#endif
-
 #define XXX KC_NO
 
 #define LAYOUT( \

keyboards/hadron/ver2/ver2.c

@@ -1,4 +1,4 @@
-#include "ver2.h"
+#include "quantum.h"
 
 #ifdef OLED_ENABLE
 oled_rotation_t oled_init_kb(oled_rotation_t rotation) { return OLED_ROTATION_180; }

keyboards/hadron/ver2/ver2.h

@@ -1,3 +0,0 @@
-#pragma once
-
-#include "hadron.h"

keyboards/hadron/ver3/ver3.c

@@ -13,7 +13,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-#include "ver3.h"
+#include "quantum.h"
 
 
 #ifdef RGB_MATRIX_ENABLE

keyboards/hadron/ver3/ver3.h

@@ -1,18 +0,0 @@
-/* Copyright 2018 ishtob
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-#pragma once
-
-#include "hadron.h"