Update libbpf-rs and libbpf-cargo to 0.22.0

Summary:
Update both `libbpf-rs` and `libbpf-cargo` to version `0.22.0`. The skeleton
generation code introduced separate `*_mut()` variants for a few accessors, so
we have to adjust a few clients.

Reviewed By: zertosh

Differential Revision: D51856567

fbshipit-source-id: 92ab0759f16f472ce02854272875983498deb926

below/Cargo.toml

@@ -30,7 +30,7 @@ cursive = { version = "0.20.0", features = ["crossterm-backend"], default-featur
 dump = { package = "below-dump", version = "0.7.1", path = "dump" }
 futures = { version = "0.3.28", features = ["async-await", "compat"] }
 indicatif = { version = "0.17.6", features = ["improved_unicode", "rayon", "tokio"] }
-libbpf-rs = "0.21.2"
+libbpf-rs = "0.22"
 libc = "0.2.139"
 model = { package = "below-model", version = "0.7.1", path = "model" }
 once_cell = "1.12"
@@ -52,7 +52,7 @@ maplit = "1.0"
 portpicker = "0.1.1"
 
 [build-dependencies]
-libbpf-cargo = "0.21.2"
+libbpf-cargo = "0.22"
 
 [features]
 enable_backtrace = []