ARM: ep93xx: ts72xx: allow rtc-m48t86 to manage its own resources

The rtc-m48t86 driver can now handle its own resources and do the
read/write operations internally.

Pass the necessary resources to the driver and remove the m48t86_ops
platform data.

Remove the, then unnecessary, static remapping for the registers.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>