INT 7F - Alloy NTNX, MW386 - RELEASE SEMAPHORE
        AH = 02h
        DS:DX -> ASCIZ semaphore name (max 64 bytes)
Return: AL = status
            00h successful
            01h invalid function
            02h semaphore locked by other user
                AH = semaphore owner
            03h unable to unlock semaphore
            05h target PC did not respond
SeeAlso: AH=01h,AH=42h