3006 VERIFY[S,U,P] and ASSERT[S,U,P] frequently check if first argument is zero

@@ -161,11 +161,11 @@
 {
         dsl_sync_task_t *dst;
         dsl_pool_t *dp = dstg->dstg_pool;
         uint64_t quota, used;
 
-        ASSERT3U(dstg->dstg_err, ==, 0);
+        ASSERT0(dstg->dstg_err);
 
         /*
          * Check for sufficient space.  We just check against what's
          * on-disk; we don't want any in-flight accounting to get in our
          * way, because open context may have already used up various