staging: comedi: hwdrv_apci3120: do comedi_handle_events() at end of interrupt

Currently comedi_handle_events() is done by both the DMA and non-DMA helper
functions that are called by the interrupt handler. For aesthetics, move
the comedi_handle_events() to the end of the interrupt handler and do it in
one place.

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