selftests/bpf: test_progs/sockopt_sk: Remove version

mainline inclusion
from mainline-5.13-rc1
commit ff182bc5
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5EUVD
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ff182bc572cec4ca757775bf2a33a3ce8611227a

-------------------------------------------------

As pointed by Andrii Nakryiko, _version is useless now, remove it.
Signed-off-by: NYauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: NAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210408061310.95877-1-yauheni.kaliuta@redhat.com
(cherry picked from commit ff182bc5)
Signed-off-by: NWang Yufen <wangyufen@huawei.com>

tools/testing/selftests/bpf/progs/sockopt_sk.c

@@ -6,7 +6,6 @@
 #include <bpf/bpf_helpers.h>
 
 char _license[] SEC("license") = "GPL";
-__u32 _version SEC("version") = 1;
 
 #ifndef PAGE_SIZE
 #define PAGE_SIZE 4096