INT 6F - HP Vectra EX-BIOS - "F_IO_CTRL SF_CREATE_EVENT" - SET EVENT HANDLER
	AX = 0408h
	BP = driver ID (see #03741) for V_LPOINTER, V_LTOUCH, V_LTABLET
	ES:SI -> new event handler (see AH=00h"HP Vectra")
	DX = new handler's DS
Return: AH = status (see #03744)
	ES:SI -> old event handler
	DX = old handler's DS
	BP,DS destroyed
Desc:	specify routine to be called on logical device events
Note:	when events occur, the event handler is called with the same registers
	  as the "F_ISR" function on AH=00h"HP Vectra"
SeeAlso: AH=00h"HP Vectra",AX=0400h"SF_LOCK",AX=0406h"SF_TRACK_OFF"
SeeAlso: AX=040Ah"SF_EVENT_ON",AX=040Ch"SF_EVENT_OFF",AH=06h"F_SAMPLE"