bpf: move BPF_(DIS)ALLOW from block.c to bpf_net_helpers.h am: 1745e54d5d am: e00be1f4a9

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/3226107

Change-Id: I2a6fcf61906c4920ae641b8c8677f48bad5abe78
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>