EX-7601 ofd: add chunk rounding to read

EX-7601 ofd: add chunk rounding to read

We need to round all niobufs to chunk size in the read
process, so we read in the full chunk.

dt_bufs_get sets up the local niobuf for the read, so we
round before calling it.

This patch is a partial implementation of unaligned read
support, and breaks compression testing until the next few
patches are landed.  So this patch temporarily adds the
compression tests to ALWAYS_EXCEPT.

Signed-off-by: Patrick Farrell <pfarrell@whamcloud.com>
Change-Id: I587a519db4dae983db5db1d690e63e15bc010b7e
Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/52867
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Artem Blagodarenko <ablagodarenko@ddn.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>