i2c: i801: Improve disabling runtime pm

Setting the autosuspend delay to a negative value disables runtime pm in
a little bit smarter way, because we need no cleanup when removing the
driver. Note that this is safe when reloading the driver, because the
call to pm_runtime_set_autosuspend_delay() in probe() will reverse the
effect. See update_autosuspend() for details.

Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>