Fix typo in comment.

Author: Etsuro Fujita

src/backend/storage/ipc/latch.c

@@ -570,7 +570,7 @@ CreateWaitEventSet(MemoryContext context, int nevents)
 	 * Use MAXALIGN size/alignment to guarantee that later uses of memory are
 	 * aligned correctly. E.g. epoll_event might need 8 byte alignment on some
 	 * platforms, but earlier allocations like WaitEventSet and WaitEvent
-	 * might not sized to guarantee that when purely using sizeof().
+	 * might not be sized to guarantee that when purely using sizeof().
 	 */
 	sz += MAXALIGN(sizeof(WaitEventSet));
 	sz += MAXALIGN(sizeof(WaitEvent) * nevents);