Change keyboard level include guards to pragma once (#14248)

* Change keyboard level include guards to `pragma once`

And clean up a lot of layout macros

* Oops

* Remove dangling endif

keyboards/four_banger/config.h

@@ -1,5 +1,4 @@
-#ifndef CONFIG_H
-#define CONFIG_H
+#pragma once
 
 #include "config_common.h"
 
@@ -45,5 +44,3 @@
 #define RGBLIGHT_SAT_STEP 8
 #define RGBLIGHT_VAL_STEP 8
 #endif
-
-#endif

keyboards/four_banger/four_banger.h

@@ -1,14 +1,11 @@
-#ifndef KB_H
-#define KB_H
+#pragma once
 
 #include "quantum.h"
 
 #define LAYOUT_ortho_2x2( \
-  K00, K01, \
-  K10, K11  \
+    k00, k01, \
+    k10, k11 \
 ) { \
-  { K00, K01 }, \
-  { K10, K11 }  \
+    { k00, k01 }, \
+    { k10, k11 } \
 }
-
-#endif