Generate data for PGO optimization of eBPF binaries

Proposal:
1) Convert bpf_xdp_dsr.o to bpf_xdp_dsr.sys.
2) Load the resulting driver, populate its various maps.
3) Use BPF_PROG_TEST_RUN to pass packet data to the program.

This test harness can serve two purposes:
1) Stress test for eBPF for Windows. - this will be covered by #2097, #2099 and #2150.
2) Allow us to generate PGO training data.

Start by tracing how bpf_xdp_dsr.o is built and how eBPF programs are loaded on Windows, then inspect the BPF_PROG_TEST_RUN entry point. The work is done when the resulting bpf_xdp_dsr.sys can be loaded, its maps populated, packet data passed through the program, and repeatable PGO training data generated.

Written by the indexing model from the issue text.