Remove useless "ifdef KEYBOARD_*" (#20078)

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

keyboards/buzzard/buzzard.c

@@ -1,3 +0,0 @@
-// Copyright 2021 Christoph Rehmann (crehmann)
-// SPDX-License-Identifier: GPL-2.0-or-later
-#include "buzzard.h"

keyboards/buzzard/buzzard.h

@@ -1,9 +0,0 @@
-// Copyright 2021 Christoph Rehmann (crehmann)
-// SPDX-License-Identifier: GPL-2.0-or-later
-#pragma once
-
-#include "quantum.h"
-
-#if defined(KEYBOARD_buzzard_rev1)
-#   include "rev1.h"
-#endif

keyboards/buzzard/rev1/rev1.h

@@ -2,7 +2,7 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 #pragma once
 
-#include "buzzard.h"
+#include "quantum.h"
 
 /* This a shortcut to help you visually see your layout.
  *