V4L/DVB (13976): [STV090x] Added mutex protection around tuner I2C access.

With this change it is possible to have the same I2C address for both tuners.

Signed-off-by: Andreas Regel <andreas.regel@gmx.de>
Signed-off-by: Manu Abraham <manu@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/dvb/frontends/stv090x_priv.h b/drivers/media/dvb/frontends/stv090x_priv.h
index d385426..5b780c8 100644
--- a/drivers/media/dvb/frontends/stv090x_priv.h
+++ b/drivers/media/dvb/frontends/stv090x_priv.h
@@ -235,6 +235,7 @@
 	u8			i2c_addr;
 
 	struct mutex		demod_lock; /* Lock access to shared register */
+	struct mutex		tuner_lock; /* Lock access to tuners */
 	s32			mclk; /* Masterclock Divider factor */
 	u32			dev_ver;