README-devel.md: drop mantle bump instructions
And simplify kola hacking instructions.
# Adding/Updating kola Tests in coreos-assembler
-For adding tests to `kola` for use in `coreos-assembler` please see the [kola test quickstart](https://github.com/coreos/mantle/blob/master/kola/README.md). After adding/updating tests in `kola` follow the `Updating Mantle` section in this document to pull in your new or updated tests into `coreos-assembler`.
+For adding tests to `kola`, please see the [kola test quickstart](https://github.com/coreos/coreos-assembler/blob/master/mantle/kola/README.md).
-
-# Updating Mantle
-
-Mantle houses a number of tools used within `coreos-assembler`. As an example, `kola` is part of mantle. Because of this it's required that `kola` tests are added in the upstream `kola` repo first, then synced into `coreos-assembler`. For more information on what tools are used please see the [README.md](README.md).
-
-To update the `mantle` checkout within `coreos-assembler` the following steps must be done:
-
-1. Update the `mantle/` checkout in the `coreos-assembler` repo to the version you expect
-2. Add and commit the `mantle/` directory
-3. Update the local submodule
-4. PR your result
-
-Here is an example for updating `mantle` to the latest code from it's own `master`:
-```
-$ pushd mantle
-<snip/>
-$ git pull origin master
-<snip/>
-$ popd
-<snip/>
-$ git commit -m "mantle: bump to current master (e7ab794)" mantle/
-[ok 9236366] mantle: bump to current master (e7ab794)
- 1 file changed, 1 insertion(+), 1 deletion(-)
-$ git submodule update -- mantle
-# Verify it's what you expect
-$ cat .git/modules/mantle/HEAD
-e7ab794c28cfd5d9d65ec34245aceaff92281be2
-$ git push origin $YOURBRANCH
-# Open PR
-```
-
-You can test the results by doing a build. See `Building the cosa container image locally` in [README.md](README.md#building-the-cosa-container-image-locally)
+You can then run `make` to build your modifications.
# Running Unit Tests
