5045 use atomic_{inc,dec}_* instead of atomic_add_*

@@ -1821,13 +1821,13 @@
         spa_t *spa = zio->io_spa;
 
         if (error) {
                 if ((BP_GET_LEVEL(bp) != 0 || DMU_OT_IS_METADATA(type)) &&
                     type != DMU_OT_INTENT_LOG)
-                        atomic_add_64(&sle->sle_meta_count, 1);
+                        atomic_inc_64(&sle->sle_meta_count);
                 else
-                        atomic_add_64(&sle->sle_data_count, 1);
+                        atomic_inc_64(&sle->sle_data_count);
         }
         zio_data_buf_free(zio->io_data, zio->io_size);
 
         mutex_enter(&spa->spa_scrub_lock);
         spa->spa_scrub_inflight--;