Remove the ability to install boot images by bootclasspath_fragments. am:...

Remove the ability to install boot images by bootclasspath_fragments. am: b47caccb am: 68b769d7 am: dad2efc3 am: 6c85ee18

Original change: https://android-review.googlesource.com/c/platform/build/soong/+/2585513



Change-Id: I338a9a348c1d91caaa2f09083250d361014fb171
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>