BpfUtils.h - add back SKIP_IF_BPF_NOT_SUPPORTED macro am: 67fa2073ff am: 625c2c6bc6

Original change: https://android-review.googlesource.com/c/platform/system/bpf/+/1631935

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I8d84f5368f2f9fa78b136d67dc92587cf05e3b81