staging: comedi: ni_daq_700: change the 'attach' printk's to dev_printk's

Use the dev_printk() routines to output the kernel messages in the
attach routine.

The main 'attach' message had a level of KERN_ERR, I believe it should
have been KERN_INFO. Also, move that message to the end of the attach
so it only gets displayed if the attach is successful.

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