osd: fix bench block size

The command was declared to take 'size' in dumpling, but was trying to
read 'bsize' instead, so it always used the default of 4MiB. Change
the bench command to read 'size', so it matches what existing clients
are sending.

Fixes: #6795
Backport: emperor, dumpling
Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
Merge pull request #854 from ceph/wip-osd-bench-size

osd: fix bench block size

Reviewed-by: Dan Mick <dan.mick@inktank.com>
test: use older names for module setup/teardown

setUp and tearDown require nosetests 0.11, but 0.10.4 is the latest on
centos. Rename to use the older aliases, which still work with newer
versions of nosetests as well.

Fixes: #6368
Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
Merge branch 'next'