USB: cdc-wdm: fix misuse of logical operation in place of bitop

commit 0cdfb819 upstream.

CC: Greg Kroah-Hartman <gregkh@suse.de>
CC: Oliver Neukum <oliver@neukum.org>
CC: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Bjørn Mork <bjorn@mork.no>

drivers/usb/class/cdc-wdm.c

@@ -314,7 +314,7 @@ static ssize_t wdm_write
 	if (r < 0)
 		goto outnp;
 
-	if (!file->f_flags && O_NONBLOCK)
+	if (!(file->f_flags & O_NONBLOCK))
 		r = wait_event_interruptible(desc->wait, !test_bit(WDM_IN_USE,
 								&desc->flags));
 	else