MPC8315ERDB: Enable DHCP support

Enable DHCP support for this board.
Signed-off-by: NEd Bartosh <ed.bartosh@linux.intel.com>
Signed-off-by: NMarek Vasut <marex@denx.de>
Signed-off-by: NTom Rini <trini@konsulko.com>

configs/MPC8315ERDB_defconfig

@@ -13,6 +13,7 @@ CONFIG_CMD_PCI=y
 CONFIG_CMD_SATA=y
 CONFIG_CMD_USB=y
 # CONFIG_CMD_SETEXPR is not set
+CONFIG_CMD_DHCP=y
 CONFIG_CMD_MII=y
 CONFIG_CMD_PING=y
 CONFIG_CMD_DATE=y