Patch from Lennert Buytenhek

This patch adds support for the Intel ixp23xx series of CPUs. The
ixp23xx is an XSC3 based CPU with 512K of L2 cache, a 64bit 66MHz PCI
interface, two DDR RAM interfaces, QDR RAM interfaces, two gigabit
MACs, two 10/100 MACs, expansion bus, four microengines, a Media and
Switch Fabric unit almost identical to the one on the ixp2400, two
xscale (8250ish) UARTs and a bunch of other stuff.

This patch adds the core ixp23xx support code, and support for the
ADI Engineering Roadrunner, Intel IXDP2351, and IP Fabrics Double
Espresso platforms.

Signed-off-by: Deepak Saxena
Signed-off-by: Lennert Buytenhek
Signed-off-by: Russell King