ppc4xx: Add MII mode support to the EMAC RGMII Bridge This patch adds support for placing the RGMII bridge on the PPC405EX(r) into MII/GMII mode and allows a board-specific configuration to specify the bridge mode at compile-time. Signed-off-by: Grant Erickson <gerickson@nuovations.com> Signed-off-by: Stefan Roese <sr@denx.de>