tty: Replace TTY_IO_ERROR bit tests with tty_io_error()

Abstract TTY_IO_ERROR status test treewide with tty_io_error().
NB: tty->flags uses atomic bit ops; replace non-atomic bit test
with test_bit().

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index 2f12bb9..f23c2a1 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -1334,7 +1334,7 @@
 
 	if (tty->index == MXSER_PORTS)
 		return -ENOIOCTLCMD;
-	if (test_bit(TTY_IO_ERROR, &tty->flags))
+	if (tty_io_error(tty))
 		return -EIO;
 
 	control = info->MCR;
@@ -1361,7 +1361,7 @@
 
 	if (tty->index == MXSER_PORTS)
 		return -ENOIOCTLCMD;
-	if (test_bit(TTY_IO_ERROR, &tty->flags))
+	if (tty_io_error(tty))
 		return -EIO;
 
 	spin_lock_irqsave(&info->slock, flags);
@@ -1715,8 +1715,7 @@
 		return 0;
 	}
 
-	if (cmd != TIOCGSERIAL && cmd != TIOCMIWAIT &&
-			test_bit(TTY_IO_ERROR, &tty->flags))
+	if (cmd != TIOCGSERIAL && cmd != TIOCMIWAIT && tty_io_error(tty))
 		return -EIO;
 
 	switch (cmd) {