Change KVM to use e1000

add -net nic,model=e1000 in start_kvm and in the suggested command as
output by image_to_vm.sh

Signed-off-by: Olof Johansson <olofj@chromium.org>

BUG=none
TEST=Boot an image, run lspci in a terminal, see intel nic

Review URL: http://codereview.chromium.org/3779007

Change-Id: Id7f614adec0ae69b8f4de152832538a13ea4cbad

image_to_vm.sh

@@ -280,7 +280,7 @@ fi
 
 if [ "${FLAGS_format}" == "qemu" ]; then
   echo "If you have qemu-kvm installed, you can start the image by:"
-  echo "sudo kvm -m ${FLAGS_mem} -vga std -pidfile /tmp/kvm.pid -net nic " \
+  echo "sudo kvm -m ${FLAGS_mem} -vga std -pidfile /tmp/kvm.pid -net nic,model=e1000 " \
        "-net user,hostfwd=tcp::922-:22 \\"
   echo "        -hda ${FLAGS_to}/${DEFAULT_QEMU_IMAGE}"
 fi

lib/cros_vm_lib.sh

@@ -51,7 +51,7 @@ function start_kvm() {
       -vga std \
       -pidfile "${KVM_PID_FILE}" \
       -daemonize \
-      -net nic \
+      -net nic,model=e1000 \
       ${nographics} \
       ${snapshot} \
       -net user,hostfwd=tcp::${FLAGS_ssh_port}-:22 \