85xx: Added P1020 Processor Support.

P1020 is another member of QorIQ series of processors which falls in ULE
category. It is an e500 based dual core SOC.

Being a scaled down version of P2020 it has following differences:
- 533MHz - 800MHz core frequency.
- 256Kbyte L2 cache
- Ethernet controllers with classification capabilities.
Also the SOC is pin compatible with P2020

Signed-off-by: Poonam Aggrwal <poonam.aggrwal@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>