selftests/bpf: Remove verifier/xdp_direct_packet_access.c, converted to...

selftests/bpf: Remove verifier/xdp_direct_packet_access.c, converted to progs/verifier_xdp_direct_packet_access.c

Removing verifier/xdp_direct_packet_access.c.c as it was automatically converted to use
inline assembly in the previous commit. It is available in
progs/verifier_xdp_direct_packet_access.c.c.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230328020813.392560-3-eddyz87@gmail.com