Removed mbed.h global include

Author: AGlass0fMilk

usb/device/targets/TARGET_NORDIC/TARGET_MCU_NRF52840/USBPhyHw.h

@@ -18,9 +18,12 @@
 #ifndef USBPHYHW_H
 #define USBPHYHW_H
 
-#include "mbed.h"
 #include "USBPhy.h"
 
+#include <string.h>
+#include "platform/mbed_power_mgmt.h"
+
+
 extern "C" {
 #include "nrf_drv_usbd.h"
 #include "nrfx_power.h"