staging: comedi: me4000: remove struct me4000_ao_info

The me4000_ao_info in the boardinfo struct is used to indicate
the number of analog output channels and a couple other details
about them. Remove the extra struct and absorb the data into the
boardinfo struct.

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