configs/qemu_ppc_e500mc: enable dhcp on network interface

Add a virtio-net-pci device with a user mode host network backend

Cc: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

board/qemu/ppc-e500mc/readme.txt

@@ -1,5 +1,5 @@
 Run the emulation with:
 
- qemu-system-ppc -M ppce500 -cpu e500mc -m 256 -kernel output/images/uImage -drive file=output/images/rootfs.ext2,if=virtio,format=raw -append "console=ttyS0 rootwait root=/dev/vda" -serial mon:stdio -nographic # qemu_ppc_e500mc_defconfig
+ qemu-system-ppc -M ppce500 -cpu e500mc -m 256 -kernel output/images/uImage -drive file=output/images/rootfs.ext2,if=virtio,format=raw -net nic,model=virtio-net-pci -net user -append "console=ttyS0 rootwait root=/dev/vda" -serial mon:stdio -nographic # qemu_ppc_e500mc_defconfig
 
 The login prompt will appear in the terminal that started Qemu.

configs/qemu_ppc_e500mc_defconfig

@@ -2,7 +2,8 @@
 BR2_powerpc=y
 BR2_powerpc_e500mc=y
 
-# Serial port config
+# System
+BR2_SYSTEM_DHCP="eth0"
 BR2_TARGET_GENERIC_GETTY_PORT="ttyS0"
 
 # Image