Fix typo, should be UNIV_SYNC_DEBUG.

storage/innodb_plugin/trx/trx0sys.c

@@ -241,9 +241,9 @@ trx_sys_create_doublewrite_buf(void)
 {
 	buf_block_t*	block;
 	buf_block_t*	block2;
-#ifdef UNIV_DEBUG
+#ifdef UNIV_SYNC_DEBUG
 	buf_block_t*	new_block;
-#endif /* UNIV_DEBUG */
+#endif /* UNIV_SYNC_DEBUG */
 	byte*	doublewrite;
 	byte*	fseg_header;
 	ulint	page_no;
@@ -346,9 +346,9 @@ trx_sys_create_doublewrite_buf(void)
 			the page position in the tablespace, then the page
 			has not been written to in doublewrite. */
 
-#ifdef UNIV_DEBUG
+#ifdef UNIV_SYNC_DEBUG
 			new_block =
-#endif /* UNIV_DEBUG */
+#endif /* UNIV_SYNC_DEBUG */
 			buf_page_get(TRX_SYS_SPACE, 0, page_no,
 				     RW_X_LATCH, &mtr);
 			buf_block_dbg_add_level(new_block,