USB Suspend for arm_atsam protocol

Rewrote USB state tracking for implementation of suspend state.
Updated suspend.c in entirety.
Main subtasks (generally hardware related) are now run prior to keyboard task.

tmk_core/protocol/arm_atsam/usb/ui.c

@@ -52,8 +52,6 @@
 #include "samd51j18a.h"
 #include "ui.h"
 
-volatile uint8_t usb_state;
-
 //! Sequence process running each \c SEQUENCE_PERIOD ms
 #define SEQUENCE_PERIOD 150
 
@@ -72,12 +70,12 @@ static void ui_wakeup_handler(void)
 
 void ui_init(void)
 {
-    usb_state = USB_STATE_POWERUP;
+
 }
 
 void ui_powerdown(void)
 {
-    usb_state = USB_STATE_POWERDOWN;
+
 }
 
 void ui_wakeup_enable(void)
@@ -92,7 +90,7 @@ void ui_wakeup_disable(void)
 
 void ui_wakeup(void)
 {
-    usb_state = USB_STATE_POWERUP;
+
 }
 
 void ui_process(uint16_t framenumber)

tmk_core/protocol/arm_atsam/usb/ui.h

@@ -47,12 +47,6 @@
 #ifndef _UI_H_
 #define _UI_H_
 
-extern volatile uint8_t usb_state;
-
-#define USB_STATE_UNKNOWN 0
-#define USB_STATE_POWERDOWN 1
-#define USB_STATE_POWERUP 2
-
 //! \brief Initializes the user interface
 void ui_init(void);