BpfLoader: split legacy bpfloader into 3 phases, simplify arguments am: dd4bd2d655

Original change: https://android-review.googlesource.com/c/platform/system/bpf/+/3212376

Change-Id: I5e5629819e277066426919d6e12d11b5bbd8dcb9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>