mainline inclusion
from mainline-5.15-rc1
commit b0588390
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=b0588390dbcedcd74fab6ffb8afe8d52380fd8b6

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

Move CO-RE logic into separate file.
The internal interface between libbpf and CO-RE is through
bpf_core_apply_relo_insn() function and few structs defined in relo_core.h.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210721000822.40958-5-alexei.starovoitov@gmail.com
(cherry picked from commit b0588390)
Signed-off-by: NWang Yufen <wangyufen@huawei.com>