rust/chg/build.rs

phases: change the way we warm the phasecache in repocache

Same logic as for the previous chngeset. We are about to rename and change the
method used here.

fn main() {
    cc::Build::new()
        .warnings(true)
        .file("src/sendfds.c")
        .file("src/sighandlers.c")
        .compile("procutil");
}