LU-1095 debug: quiet noisy console error messages

Quiet a number of overly noisy and unhelpful console error
messages.  Improve the format of other nearby errors.

In the case of {lod,lov}_fix_desc_stripe_size(), this doesn't
even need a console message unless it is actually changing
some stripe size that is below the minimum.  Typically it is
only zero and is being bumped up to the default value.

Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Change-Id: I0830e514c426080b8c3446c0a1a359c313b530d9
Reviewed-on: http://review.whamcloud.com/6264
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Bobi Jam <bobijam@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>