LU-2800 autoconf: remove bio_endio args test

LU-2800 autoconf: remove bio_endio args test

Since linux kernel version 2.6.24 the bio api has been
taking one less argument than in previous versions. Since
we no longer support kernels earlier than 2.6.32 we can
drop this test and simplify the code using the bio api.

Signed-off-by: James Simmons <uja.ornl@gmail.com>
Change-Id: Ieedface5065d660284c5dfb9a61cb81e4174c61d
Reviewed-on: http://review.whamcloud.com/8104
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>