The power manager and core clock registers aren't present in PXA3
CPUs.  Move them out of pxa-regs.h into pxa2xx-regs.h, and include
pxa2xx-regs.h where necessary.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

PXA3 has a different memory controller from PXA2 platforms.  Avoid
clashing definitions by moving the PXA2 definitions to pxa2xx-regs.h
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>