ptp: vmclock: Add .owner to vmclock_miscdev_fops

Without the .owner field, the module can be unloaded while /dev/vmclock0
is open, leading to an oops.

Fixes: 2050327 ("ptp: Add support for the AMZNC10C 'vmclock' device")
Cc: stable@vger.kernel.org
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: dwmw2

drivers/ptp/ptp_vmclock.c

@@ -414,6 +414,7 @@ static ssize_t vmclock_miscdev_read(struct file *fp, char __user *buf,
 }
 
 static const struct file_operations vmclock_miscdev_fops = {
+	.owner = THIS_MODULE,
 	.mmap = vmclock_miscdev_mmap,
 	.read = vmclock_miscdev_read,
 };