Sync contrib service with static systemd args

And add comments in both places so we remember
to keep them in sync.

Signed-off-by: Colin Walters <[email protected]>

Author: cgwalters

Diff for: contrib/packaging/bootloader-update.service

@@ -6,7 +6,10 @@ Documentation=https://github.com/coreos/bootupd
 Type=oneshot
 ExecStart=/usr/bin/bootupctl update
 RemainAfterExit=yes
+# Keep this stuff in sync with SYSTEMD_ARGS_BOOTUPD in general
+ProtectHome=yes
 MountFlags=slave
+KillMode=mixed
 
 [Install]
 WantedBy=multi-user.target

Diff for: src/cli/bootupctl.rs

@@ -11,6 +11,7 @@ static SYSTEMD_ARGS_BOOTUPD: &[&str] = &[
     "bootupd",
     "--property",
     "PrivateNetwork=yes",
+    // Keep this stuff in sync with bootloader-update.service
     "--property",
     "ProtectHome=yes",
     // While only our main process during update catches SIGTERM, we don't