Don't register repair writes in the trim map.

Don't register repair writes in the trim map.

The trim map inflight writes tree assumes non-conflicting writes, i.e.
that there will never be two simultaneous write I/Os to the same range
on the same vdev. This seemed like a sane assumption; however, in
actual testing, it appears that repair I/Os can very well conflict
with "normal" writes.

I'm not quite sure if these conflicting writes are supposed to happen
or not, but in the mean time, let's ignore repair writes for now. This
should be safe considering that, by definition, we never repair blocks
that are freed.

Reviewed by:	pjd (mentor)
Approved by:	pjd (mentor)
Obtained from:	Source: https://github.com/dechamps/zfs/commit/6a3cebaf7c5fcc92007280b5d403c15d0e61dfe3