ARM: at91/i2c: change id to let i2c-at91 work

The i2c core driver will turn the platform device ID to busnum
When using platfrom device ID as -1, it means dynamically assigned
the busnum. When writing code, we need to make sure the busnum,
and call i2c_register_board_info(int busnum, ...) to register device
if using -1, we do not know the value of busnum

In order to solve this issue, set the platform device ID as a fix number
Here using 0 to match the busnum used in i2c_regsiter_board_info()

Signed-off-by: Bo Shen <voice.shen@atmel.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
diff --git a/arch/arm/mach-at91/at91sam9rl_devices.c b/arch/arm/mach-at91/at91sam9rl_devices.c
index 3d2c81d..5047bdc 100644
--- a/arch/arm/mach-at91/at91sam9rl_devices.c
+++ b/arch/arm/mach-at91/at91sam9rl_devices.c
@@ -347,7 +347,7 @@
 
 static struct platform_device at91sam9rl_twi_device = {
 	.name		= "i2c-at91sam9g20",
-	.id		= -1,
+	.id		= 0,
 	.resource	= twi_resources,
 	.num_resources	= ARRAY_SIZE(twi_resources),
 };