i2c: Fix platform driver hotplug/coldplug

Since 43cc71eed1250755986da4c0f9898f9a635cb3bf, the platform
modalias is prefixed with "platform:". Add MODULE_ALIAS() to the
hotpluggable I2C platform drivers, to allow module auto loading.

[ db: add some more drivers ]

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c
index 3ca19fc..7c1b762 100644
--- a/drivers/i2c/busses/i2c-gpio.c
+++ b/drivers/i2c/busses/i2c-gpio.c
@@ -220,3 +220,4 @@
 MODULE_AUTHOR("Haavard Skinnemoen <hskinnemoen@atmel.com>");
 MODULE_DESCRIPTION("Platform-independent bitbanging I2C driver");
 MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:i2c-gpio");