added (mostly) out-of-the box StorCLI integration

Hey.

"Mostly" in the sense, that it may be necessary to configure the pathname to the StorCLI executable.

Apart from that, I've just built that and tested it on one our our nodes does seem to work.
Similarly, it does seem to work one nodes where the megaraid_sas module isn't loaded, in the sense that the neither the .service nor the .timer actually run (the later is even "inactive").

Uhm... any chance to get that backported to bookworm? O:-)

btw: I think the package, on remove/purge, doesn't clean up it's .prom files. Once this PR got merged, I could make a PR that does that.

Thanks,
Chris.