Revert "bpf: Fix potential call bpf_link_free() in atomic context"

This reverts commit 31f23a6a.

This change made many selftests/bpf flaky: flow_dissector, sk_lookup, sk_assign and others.
There was no issue in the code.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>