mctp i2c: drop check because i2c_unregister_device() is NULL safe

No need to check the argument of i2c_unregister_device() because the
function itself does it.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://patch.msgid.link/20241202082713.9719-1-wsa+renesas@sang-engineering.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: Wolfram Sang

drivers/net/mctp/mctp-i2c.c

@@ -177,8 +177,7 @@ static struct mctp_i2c_client *mctp_i2c_new_client(struct i2c_client *client)
 	return mcli;
 err:
 	if (mcli) {
-		if (mcli->client)
-			i2c_unregister_device(mcli->client);
+		i2c_unregister_device(mcli->client);
 		kfree(mcli);
 	}
 	return ERR_PTR(rc);