assemble_vintf: accept --kernel for manifests.

Add KernelInfo to HalManifest object.

The final verified_assembled_vendor_manifest.xml will contain
<kernel> information for compatibility check during OTA.

Bug: 111125947
Test: build verified_assembled_vendor_manifest.xml

Change-Id: If5a3124b6cbed4da9b2038c30274c223ee52b259
9 files changed