Instead of remembering if the page was changed, just compare the current
page to the saved one. This is easier and has the advantage to save a
register write if the page was already restored.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>