staging: comedi: addi_apci_1032: remove send_sig() use

The addi-data drivers use send_sig() to let the user know when an
interrupt has occurred. The "standard" way to do this in the comedi
subsystem is to have a subdevice that supports asynchronous commands
and use comedi_event() to signal the user.

Remove the send_sig() usage in this driver. This also allows removing
the dev->private usage since tsk_Current was the only member still
being used in the private data.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>