[media] bt8xx: remove needless module refcounting

It is responsibility of a caller of fops->open(),
to make sure an owner of the fops is available until file is closed.
So, there is no need to lock THIS_MODULE explicitly.

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/pci/bt8xx/dst_ca.c

@@ -655,7 +655,6 @@ static long dst_ca_ioctl(struct file *file, unsigned int cmd, unsigned long ioct
 static int dst_ca_open(struct inode *inode, struct file *file)
 {
 	dprintk(verbose, DST_CA_DEBUG, 1, " Device opened [%p] ", file);
-	try_module_get(THIS_MODULE);
 
 	return 0;
 }
@@ -663,7 +662,6 @@ static int dst_ca_open(struct inode *inode, struct file *file)
 static int dst_ca_release(struct inode *inode, struct file *file)
 {
 	dprintk(verbose, DST_CA_DEBUG, 1, " Device closed.");
-	module_put(THIS_MODULE);
 
 	return 0;
 }