Add product manifest.

- Rename framework_manifest.xml to system_manifest.xml since that's more accurate.
- Add product_manifest.xml to base_product.mk
- Add product_manifest.xml to verified_assembled_framework_manifest.xml to check
  it at build time.

Bug: 126770403
Bug: 130714844
Bug: 80547152

Test: build and inspect output
Test: lshal

Change-Id: I1b447d8c36f72768e28e9bcaa4d06afdeba08c2a