ARM: config: Switch PXA27x platforms to use PXA RTC driver

With the SA1100 and PXA RTC drivers be mutually exclusive and no
longer sharing hardware, PXA27x/PXA3xx platforms must use the PXA RTC
driver as the SA1100 platform device is no longer registered.

This change should be almost transparent to userspace. Former users of
pxa-rtc should be aware that 2 RTCs will be available on their kernels,
rtc0 being sa1100-rtc and rtc1 being pxa-rtc. Any userspace relying on
the fact that rtc0 was pxa-rtc should be fixed.

As a consequence:
 - the first reboot after the switch will have the wrong time,
 - on dual boot platform where the other OS programs some logic into the
   sa1100 rtc IP, a lack of fix in userspace, ie. a kernel changing
   sa1100-rtc thinking it is pxa-rtc could have dire consequence, such
   as wiping the other OS data partition.

(Thanks to Robert Jarmik for help on the above commit text.)

Signed-off-by: Rob Herring <[email protected]>
Acked-by: Robert Jarzmik <[email protected]>
Cc: Daniel Mack <[email protected]>
Cc: Haojian Zhuang <[email protected]>
Cc: Sergey Lapin <[email protected]>
Cc: Russell King <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Philipp Zabel <[email protected]>
Signed-off-by: Alexandre Belloni <[email protected]>
6 files changed