INT 21 - DR DOS $IDLE$ - IOCTL - DYNAMIC IDLE DETECTION CONTROL

	AX = 4403h
	BX = file handle referencing character device $IDLE$
	CX = number of bytes to write (0004h)
	DS:DX -> $IDLE$ IOCTL structure (see #04113)
Return: CF clear if successful
	    AX = number of bytes actually written
	CF set on error
	    AX = error code (01h,05h,06h,0Dh) (see #01680 at AH=59h/BX=0000h)
Notes:	When the DR DOS IBMBIO.COM detects the presence of the $IDLE$ device
	  during startup, it will retrieve the address of the idle state
	  data area via INT 21/AX=4458h and pass it along to the $IDLE$ device
	  driver by calling this function.