libata: end the r-word

Prompted by the social effort in the US to discourage usage of the
adjective "retarded".

In this case we needlessly anthropomorphize hard drives.  The
implication is that due to design deficiencies in the device reset
recovery time is negatively impacted.  We can simply clearly state that
fact.  "Exceptional devices cause outliers in reset recovery time." This
steers clear of any unintended comparison of such devices to humans with
cognitive disabilities.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>