Added new Drivers/USB/LowLevel/Device.c file to house Device mode specific...

Added new Drivers/USB/LowLevel/Device.c file to house Device mode specific functions that are more complicated than simple macros. Moved USB_Device_SendRemoteWakeup() to the new Device.c source file and corrected it to unfreeze and restart the USB controller clock before issuing a Remote Wakeup request.

Removed the USB_Device_IsRemoteWakeupSent() and USB_Device_IsUSBSuspended() macros, as they are now obsolete.