bpf_headers: add bpf_printf() helper macro am: 2a8bf65973

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/3249699

Change-Id: I0c16690a489faa7e3a70ad1d0ec8eda6db667a52
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>