hwmon: (lm90) use proper type for update_interval

The code handles this variable always as unsigned, so adapt the type.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c
index c9ff08d..e30a593 100644
--- a/drivers/hwmon/lm90.c
+++ b/drivers/hwmon/lm90.c
@@ -375,7 +375,7 @@
 	int kind;
 	u32 flags;
 
-	int update_interval;	/* in milliseconds */
+	unsigned int update_interval; /* in milliseconds */
 
 	u8 config_orig;		/* Original configuration register value */
 	u8 convrate_orig;	/* Original conversion rate register value */