test: selftests: Remove unused various in sockmap_verdict_prog.c

'lport' and 'rport' in bpf_prog1() of sockmap_verdict_prog.c is not
used, just remove them.

Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220113031658.633290-1-imagedong@tencent.com