ARM: 7547/4: cache-l2x0: add support for Aurora L2 cache ctrl

Aurora Cache Controller was designed to be compatible with the ARM L2
Cache Controller. It comes with some difference or improvement such
as:
- no cache id part number available through hardware (need to get it
  by the DT).
- always write through mode available.
- two flavors of the controller outer cache and system cache (meaning
  maintenance operations on L1 are broadcasted to the L2 and L2
  performs the same operation).
- in outer cache mode, the cache maintenance operations are improved and
  can be done on a range inside a page and are not limited to a cache
  line.

Tested-and-Reviewed-by: Lior Amsalem <alior@marvell.com>

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Yehuda Yitschak <yehuday@marvell.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>