[NETD-BPF#14] Move BPF map definition and utils to frameworks/libs/net/ am: b1d4888ec2 am: 18af063372 am: 8e2e81b87f

Original change: https://android-review.googlesource.com/c/platform/system/bpf/+/1869329

Change-Id: I7d2c03fdb45ab98e18fa288327b101fc7d4ed425