NAME
    IND_REMHANDLER -- Remove an input handler from the device

FUNCTION
    Remove a function previously added to the list of handler
    functions.

IO REQUEST
    io_Message      mn_ReplyPort set
    io_Device       preset by opendevice
    io_Unit         preset by opendevice
    io_Command      IND_REMHANDLER
    io_Data         a pointer to the interrupt structure.

NOTES
    This command is not immediate