board: ls1043ardb: fdt fixups for revision v7.0 boards

The LS1043ARDB rev v7.0 board replaces the AQR105 PHY on MAC9 with an
AQR113C PHY. The address of the PHY on the MDIO bus changes from 0x1 to
0x8. Enable CONFIG_OF_BOARD_FIXUP and update both u-boot and Linux device
trees to reflect this change.

Signed-off-by: Camelia Groza <camelia.groza@nxp.com>