[ci] Add om-linker to "firtool" install

Also install the OM linker as part of the minimal firtool installation.
This will be included in both the nightly and published releases.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

.github/workflows/uploadReleaseArtifacts.yml

@@ -117,10 +117,10 @@ jobs:
           json=$(echo '${{ toJSON(env) }}' | jq -c)
           echo $json
           echo "out=$json" >> $GITHUB_OUTPUT
-      - name: Add Build Config for firtool
+      - name: Add Build Config for firtool and om-linker
         id: add-build-config-firtool
         run: |
-          json='{"name":"firtool","install_target":"install-firtool","package_name_prefix":"firrtl-bin","mode":"release","assert":"OFF","shared":"OFF","stats":"ON"}'
+          json='{"name":"firtool","install_target":"install-firtool install-om-linker","package_name_prefix":"firrtl-bin","mode":"release","assert":"OFF","shared":"OFF","stats":"ON"}'
           if [[ ${{ github.event_name }} == 'schedule' ]] || [[ ${{ github.event_name }} == 'workflow_dispatch' ]]; then
             json=$(echo $json | jq -c '.assert = "ON" | .mode = "relwithdebinfo"')
           fi