mimxrt/systick: Clean up header file includes.

`systick.h` and `pendsv.h` both use MICROPY-level configuration macros, so
must include `py/mpconfig.h`.

Signed-off-by: Damien George <damien@micropython.org>

Author: dpgeorge

ports/mimxrt/pendsv.h

@@ -26,6 +26,8 @@
 #ifndef MICROPY_INCLUDED_MIMXRT_PENDSV_H
 #define MICROPY_INCLUDED_MIMXRT_PENDSV_H
 
+#include "py/mpconfig.h"
+
 enum {
     PENDSV_DISPATCH_SOFT_TIMER,  // For later & for having at least one entry
     #if MICROPY_PY_NETWORK && MICROPY_PY_LWIP

ports/mimxrt/systick.c

@@ -24,10 +24,7 @@
  * THE SOFTWARE.
  */
 
-#include "py/runtime.h"
-#include "py/mphal.h"
 #include "systick.h"
-
 #include "pendsv.h"
 #include "shared/runtime/softtimer.h"
 

ports/mimxrt/systick.h

@@ -26,6 +26,8 @@
 #ifndef MICROPY_INCLUDED_MIMXRT_SYSTICK_H
 #define MICROPY_INCLUDED_MIMXRT_SYSTICK_H
 
+#include "py/mpconfig.h"
+
 // Works for x between 0 and 16 inclusive
 #define POW2_CEIL(x) ((((x) - 1) | ((x) - 1) >> 1 | ((x) - 1) >> 2 | ((x) - 1) >> 3) + 1)