Make commit module public

I think it makes sense for us to use this in rpm-ostree directly
too at build time for example.

lib/src/commit.rs

@@ -49,7 +49,7 @@ fn process_dir_recurse(root: &Dir, path: &Utf8Path, error_count: &mut i32) -> Re
 
 /// Given a root filesystem, clean out empty directories and warn about
 /// files in /var.  /run, /tmp, and /var/tmp have their contents recursively cleaned.
-fn prepare_ostree_commit_in(root: &Dir) -> Result<()> {
+pub fn prepare_ostree_commit_in(root: &Dir) -> Result<()> {
     let mut error_count = 0;
     for path in FORCE_CLEAN_PATHS {
         if let Some(subdir) = root.open_dir_optional(path)? {

lib/src/lib.rs

@@ -40,7 +40,7 @@ pub mod tar;
 pub mod tokio_util;
 
 pub mod chunking;
-pub(crate) mod commit;
+pub mod commit;
 pub mod objectsource;
 pub(crate) mod objgv;
 #[cfg(feature = "internal-testing-api")]