Fix, consolidate PSTR aliases (#20812)

Co-authored-by: Jason Smith <jason.inet@gmail.com>
Co-authored-by: Scott Lahteine <thinkyhead@users.noreply.github.com>

Marlin/src/HAL/LPC1768/HAL.h

@@ -214,16 +214,3 @@ void HAL_clear_reset_source(void);
 uint8_t HAL_get_reset_source(void);
 
 inline void HAL_reboot() {}  // reboot the board or restart the bootloader
-
-// Add strcmp_P if missing
-#ifndef strcmp_P
-  #define strcmp_P(a, b) strcmp((a), (b))
-#endif
-
-#ifndef strcat_P
-  #define strcat_P(a, b) strcat((a), (b))
-#endif
-
-#ifndef strcpy_P
-  #define strcpy_P(a, b) strcpy((a), (b))
-#endif