dm cache: replace memcpy with struct assignment

Use struct assignment rather than memcpy in dm cache.

Signed-off-by: Joe Thornber <[e-mail]>
Signed-off-by: Alasdair G Kergon <[e-mail]>

drivers/md/dm-cache-metadata.c

···
 				 struct dm_cache_statistics *stats)
 {
 	down_read(&cmd->root_lock);
-	memcpy(stats, &cmd->stats, sizeof(*stats));
+	*stats = cmd->stats;
 	up_read(&cmd->root_lock);
 }
 
···
 				 struct dm_cache_statistics *stats)
 {
 	down_write(&cmd->root_lock);
-	memcpy(&cmd->stats, stats, sizeof(*stats));
+	cmd->stats = *stats;
 	up_write(&cmd->root_lock);
 }
 

drivers/md/dm-cache-target.c

···
 	ti->discards_supported = true;
 	ti->discard_zeroes_data_unsupported = true;
 
-	memcpy(&cache->features, &ca->features, sizeof(cache->features));
+	cache->features = ca->features;
 	ti->per_bio_data_size = get_per_bio_data_size(cache);
 
 	cache->callbacks.congested_fn = cache_is_congested;