PIIODevice registration dramatically optimization

libs/main/io_devices/piusb.h

@@ -63,7 +63,7 @@ struct usb_dev_handle;
 
 class PIP_EXPORT PIUSB: public PIIODevice
 {
-	PIIODEVICE(PIUSB)
+	PIIODEVICE(PIUSB, "usb")
 public:
 	explicit PIUSB(ushort vid = 0, ushort pid = 0);
 	virtual ~PIUSB();
@@ -160,7 +160,6 @@ public:
 	void flush();
 
 protected:
-	PIString fullPathPrefix() const {return PIStringAscii("usb");}
 	bool configureDevice(const void * e_main, const void * e_parent = 0);
 	PIString constructFullPathDevice() const;
 	void configureFromFullPathDevice(const PIString & full_path);