main: Fix systemd-generator

[monstermunchkin]

No description provided.

[stgraber]

• Let's use sed -r everywhere then (@simondeziel FYI busybox doesn't support -E).
• Let's make a function to do the BindReadOnly thing and call it for both networkd and resolved

[stgraber]

Additional bits for privileged containers:

	if grep -q 4294967295 /proc/self/uid_map; then
		echo "ProtectHome=no" >> "${dropin_dir}/lxc-service.conf"
		echo "ProtectSystem=no" >> "${dropin_dir}/lxc-service.conf"
		echo "PrivateDevices=no" >> "${dropin_dir}/lxc-service.conf"
		echo "PrivateTmp=no" >> "${dropin_dir}/lxc-service.conf"
		echo "ProtectKernelLogs=no" >> "${dropin_dir}/lxc-service.conf"
		echo "ProtectKernelModules=no" >> "${dropin_dir}/lxc-service.conf"
		echo "ReadWritePaths=" >> "${dropin_dir}/lxc-service.conf"
	fi

[stgraber]

All return calls need to be changed to return 0

[simondeziel]

* Let's use `sed -r` everywhere then (@simondeziel FYI busybox doesn't support `-E`).

There is no extended regex in there so I'd simply drop '-r'/'-E' and maybe use a more compact form like:

sed 's#/\(etc\|run\|usr/lib\)/systemd/##g'