Add 'LTS Only' build selection to main.yml and job

- Added 'LTS Only' option to workflow_dispatch build_selection
- Added 'build-lts-only' job that runs reusable LTS workflow
- Enables building only LTS kernels from the main workflow

.github/workflows/main.yml

@@ -32,6 +32,7 @@ on:
         type: choice
         options:
           - All
+          - LTS Only
           - Android12-5.10
           - Android13-5.10
           - Android13-5.15
@@ -42,6 +43,11 @@ on:
 
 jobs:
 
+  build-lts-only:
+    if: inputs.build_selection == 'LTS Only'
+    uses: ./.github/workflows/lts-kernels.yml
+    secrets: inherit
+
   build-a12-5-10:
     if: (inputs.build_selection == 'All' || inputs.build_selection == 'Android12-5.10')
     uses: ./.github/workflows/kernel-a12-5-10.yml