staging: comedi: quatech_daqp_cs: remove #define pr_fmt

There are not pr_[level] uses in this file. Remove the pr_fmt
define.

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>