i2c: Use <linux/io.h> instead of <asm/io.h>

As warned by checkpatch.pl, <linux/io.h> should be used instead of
<asm/io.h>.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index ee9da6f..6d14ac2 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -39,7 +39,7 @@
 #include <linux/init.h>
 #include <linux/dmi.h>
 #include <linux/acpi.h>
-#include <asm/io.h>
+#include <linux/io.h>
 
 
 /* PIIX4 SMBus address offsets */