media: bt8xx: avoid a needless u8 to char conversion

Instead of doing the cast, just change the type to char.

Suggested-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/pci/bt8xx/dst_common.h

@@ -138,7 +138,7 @@ struct dst_state {
 	u32 tuner_type;
 	char *tuner_name;
 	struct mutex dst_mutex;
-	u8 fw_name[8];
+	char fw_name[8];
 	struct dvb_device *dst_ca;
 };