[media] radio-si4713: Add regulator framework support

Convert the driver to use regulator framework instead of set_power callback.
This with gpio_reset platform data provide cleaner way to manage chip VIO,
VDD and reset signal inside the driver.

Signed-off-by: Jarkko Nikula <jhnikula@gmail.com>
Cc: Eduardo Valentin <eduardo.valentin@nokia.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/media/si4713.h b/include/media/si4713.h
index 99850a5..ed7353e 100644
--- a/include/media/si4713.h
+++ b/include/media/si4713.h
@@ -23,8 +23,7 @@
  * Platform dependent definition
  */
 struct si4713_platform_data {
-	/* Set power state, zero is off, non-zero is on. */
-	int (*set_power)(int power);
+	int gpio_reset; /* < 0 if not used */
 };
 
 /*