ARM: pxa: add memory resource to SA1100 RTC device

The drivers for the SA1100 and PXA RTCs are now mutually exclusive, so
add the memory resource for the sa1100-rtc device. Since the memory
resource is already present in the pxa_rtc_resources, that makes
sa1100_rtc_resources and pxa_rtc_resources equivalent, so use
pxa_rtc_resources for both devices and remove the duplicate
sa1100_rtc_resources.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Daniel Mack <daniel@zonque.org>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>