greybus: i2c-gb: fix bad message size in gb_i2c

The data_in_size variable was set to 1 for the status byte.
But now, the status byte has move to header. Then, the status byte
is "allocated" twice and cause bad message size error.
Signed-off-by: Alexandre Bailon <abailon@baylibre.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

drivers/staging/greybus/i2c-gb.c

@@ -199,7 +199,7 @@ gb_i2c_transfer_request(struct gb_connection *connection,
 	struct gb_i2c_transfer_op *op;
 	struct i2c_msg *msg;
 	u32 data_out_size = 0;
-	u32 data_in_size = 1;	/* Response begins with a status byte */
+	u32 data_in_size = 0;
 	size_t request_size;
 	void *data;
 	u16 op_count;