i2c: add a flag to mark clients as slaves

And update indentation with one more tab, sigh...
Tested-by: Andrey Danin <danindrey@mail.ru>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

include/linux/i2c.h

@@ -553,6 +553,7 @@ void i2c_unlock_adapter(struct i2c_adapter *);
 #define I2C_CLIENT_PEC		0x04	/* Use Packet Error Checking */
 #define I2C_CLIENT_TEN		0x10	/* we have a ten bit chip address */
 					/* Must equal I2C_M_TEN below */
+#define I2C_CLIENT_SLAVE	0x20	/* we are the slave */
 #define I2C_CLIENT_WAKE		0x80	/* for board_info; true iff can wake */
 #define I2C_CLIENT_SCCB		0x9000	/* Use Omnivision SCCB protocol */
 					/* Must match I2C_M_STOP|IGNORE_NAK */