staging: comedi: addi_apci_3501: board has an eeprom

The board supported by this driver has an on-board eeprom. Since
we need to read it to get the number of analog output channels,
expose the eeprom as a readable subdevice to the user.

Rename the i_ADDIDATA_InsnReadEeprom() function to give it namespace
associated with the driver.

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>