Change include guards in tmk_core/ and drivers/ to pragma once (#11240)

tmk_core/protocol/ps2_io.h

@@ -1,5 +1,4 @@
-#ifndef PS2_IO_H
-#define PS2_IO_H
+#pragma once
 
 void clock_init(void);
 void clock_lo(void);
@@ -10,5 +9,3 @@ void data_init(void);
 void data_lo(void);
 void data_hi(void);
 bool data_in(void);
-
-#endif