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/helix/local_drivers/i2c.h

@@ -1,5 +1,4 @@
-#ifndef I2C_H
-#define I2C_H
+#pragma once
 
 #include <stdint.h>
 
@@ -45,5 +44,3 @@ extern unsigned char i2c_readNak(void);
 extern unsigned char i2c_read(unsigned char ack);
 
 #define i2c_read(ack)  (ack) ? i2c_readAck() : i2c_readNak();
-
-#endif

keyboards/helix/local_drivers/serial.h

@@ -1,5 +1,4 @@
-#ifndef SOFT_SERIAL_H
-#define SOFT_SERIAL_H
+#pragma once
 
 #include <stdbool.h>
 
@@ -85,5 +84,3 @@ int  soft_serial_transaction(int sstd_index);
 #ifdef SERIAL_USE_MULTI_TRANSACTION
 int  soft_serial_get_and_clean_status(int sstd_index);
 #endif
-
-#endif /* SOFT_SERIAL_H */

keyboards/helix/local_drivers/ssd1306.h

@@ -1,5 +1,4 @@
-#ifndef SSD1306_H
-#define SSD1306_H
+#pragma once
 
 #include <stdbool.h>
 #include <stdio.h>
@@ -88,5 +87,3 @@ void matrix_write_P(struct CharacterMatrix *matrix, const char *data);
 void matrix_render(struct CharacterMatrix *matrix);
 
 bool process_record_gfx(uint16_t keycode, keyrecord_t *record);
-
-#endif