util: aio-posix: fix a typo

Cc: qemu-trivial@nongnu.org
Signed-off-by: NLi Qiang <liq3ea@gmail.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NFam Zheng <famz@redhat.com>
Message-id: 1538964972-3223-1-git-send-email-liq3ea@gmail.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

util/aio-posix.c

@@ -40,7 +40,7 @@ struct AioHandler
 
 #ifdef CONFIG_EPOLL_CREATE1
 
-/* The fd number threashold to switch to epoll */
+/* The fd number threshold to switch to epoll */
 #define EPOLL_ENABLE_THRESHOLD 64
 
 static void aio_epoll_disable(AioContext *ctx)