INT 6F - HP Vectra EX-BIOS - "F_IO_CTRL SF_UNLOCK" - RELEASE SUB-ADDRESSES
	AX = 0402h
	BP = driver ID (see #03741)
	DH,DL = major,minor address (optional)
Return: AH = status (see #03744)
	BP,DS destroyed
Desc:	release specified sub-addresses from exclusive access
Note:	this function is documented as present but unsupported in the drivers
	  V_LTABLET, V_LPOINTER, and VLTOUCH
SeeAlso: AX=0200h"HP Vectra",AX=0400h"SF_LOCK"