packaging: add a systemd unit to run every boot

This enables bootloader updates automatically on boot.
Note that the service is intentionally not enabled by default,
it should be up to the distribution to add a systemd preset if
auto-update for the bootloader is desired.

Right now RAID setups are not supported but see [1] for an example
in coreos.

[1] coreos/fedora-coreos-config#3042

contrib/packaging/bootupctl-update.service

@@ -0,0 +1,13 @@
+[Unit]
+Description=Update Bootloader on boot
+Documentation=https://github.com/coreos/bootupd
+ConditionPathExists=/dev/disk/by-label/EFI-SYSTEM
+
+[Service]
+Type=oneshot
+ExecStart=/usr/bin/bootupctl update
+RemainAfterExit=yes
+MountFlags=slave
+
+[Install]
+WantedBy=multi-user.target

contrib/packaging/bootupd.spec

@@ -21,6 +21,7 @@ BuildRequires: cargo
 BuildRequires: git
 BuildRequires: openssl-devel
 BuildRequires: systemd-devel
+BuildRequires: systemd-rpm-macros
 
 %description 
 %{summary}
@@ -31,6 +32,7 @@ BuildRequires: systemd-devel
 %{_bindir}/bootupctl
 %{_libexecdir}/bootupd
 %{_prefix}/lib/bootupd/grub2-static/
+%{_unitdir}/bootupctl-update.service
 
 %prep
 %autosetup -n %{crate}-%{version} -p1 -Sgit
@@ -53,4 +55,4 @@ make install-grub-static DESTDIR=%{?buildroot} INSTALL="%{__install} -p"
 
 %changelog
 * Tue Oct 18 2022 Colin Walters <[email protected]> - 0.2.8-3
-- Dummy changelog
+- Dummy changelog