i2c-stu300: off by one issue

If we don't find the correct rate, we want to end the loop with "i"
pointing to the last element in the array.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
diff --git a/drivers/i2c/busses/i2c-stu300.c b/drivers/i2c/busses/i2c-stu300.c
index 1f5b38b..495be45 100644
--- a/drivers/i2c/busses/i2c-stu300.c
+++ b/drivers/i2c/busses/i2c-stu300.c
@@ -498,7 +498,7 @@
 	int i = 0;
 
 	/* Locate the apropriate clock setting */
-	while (i < ARRAY_SIZE(stu300_clktable) &&
+	while (i < ARRAY_SIZE(stu300_clktable) - 1 &&
 	       stu300_clktable[i].rate < clkrate)
 		i++;