The number of register we can safely pass to at91_pm_suspend_in_sram is
limited. Instead, pass the address to the at91_pm_data structure.

The offsets are automatically generated to avoid hardcoding them.
Acked-by: NWenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>