Update RootlessKit (3.0.0)

- slirp4netns/vpnkit is no longer needed as gvisor-tap-vsock is now embedded in RootlessKit.
  slirp4netns/vpnkit is still used when installed.
- The `builtin` port driver can now correctly propagate the source IP, when
  `userland-proxy` is disabled.

Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>

hack/dockerfile/install/rootlesskit.installer

@@ -1,7 +1,7 @@
 #!/bin/sh
 
 # When updating, also update go.mod and Dockerfile accordingly.
-: "${ROOTLESSKIT_VERSION:=v2.3.6}"
+: "${ROOTLESSKIT_VERSION:=v3.0.0}"
 
 install_rootlesskit() {
 	case "$1" in

hack/make/binary-daemon

@@ -17,11 +17,6 @@ copy_binaries() {
 	for file in containerd containerd-shim-runc-v2 ctr runc docker-init rootlesskit dockerd-rootless.sh dockerd-rootless-setuptool.sh; do
 		cp -f "$(command -v "$file")" "$dir/"
 	done
-	# vpnkit might not be available for the target platform, see vpnkit stage in
-	# the Dockerfile for more information.
-	if command -v vpnkit > /dev/null 2>&1; then
-		cp -f "$(command -v vpnkit)" "$dir/"
-	fi
 }
 
 [ -z "$KEEPDEST" ] && rm -rf "$DEST"

hack/make/install-binary

@@ -17,7 +17,4 @@ source "${MAKEDIR}/.install"
 	install_binary "${DEST}/rootlesskit"
 	install_binary "${DEST}/dockerd-rootless.sh"
 	install_binary "${DEST}/dockerd-rootless-setuptool.sh"
-	if [ -f "${DEST}/vpnkit" ]; then
-		install_binary "${DEST}/vpnkit"
-	fi
 )