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

@@ -504,11 +504,11 @@
                             obj, zap->zap_m.zap_num_entries);
                         *zapp = zap;
                         return (mzap_upgrade(zapp, tx, 0));
                 }
                 err = dmu_object_set_blocksize(os, obj, newsz, 0, tx);
-                ASSERT3U(err, ==, 0);
+                ASSERT0(err);
                 zap->zap_m.zap_num_chunks =
                     db->db_size / MZAP_ENT_LEN - 1;
         }
 
         *zapp = zap;

@@ -599,11 +599,11 @@
         if (flags != 0) {
                 zap_t *zap;
                 /* Only fat zap supports flags; upgrade immediately. */
                 VERIFY(0 == zap_lockdir(os, obj, tx, RW_WRITER,
                     B_FALSE, B_FALSE, &zap));
-                VERIFY3U(0, ==, mzap_upgrade(&zap, tx, flags));
+                VERIFY0(mzap_upgrade(&zap, tx, flags));
                 zap_unlockdir(zap);
         }
 }
 
 int