build: Use patched cargo-bindgen for native32

Workaround-For: rust-lang/rust-bindgen#2991

Author: chrysn

Cargo.toml

@@ -24,7 +24,12 @@ riot-build = { version = "< 0.2.0", optional = true }
 riot-rs-core = { version = "< 0.2.0", optional = true }
 
 [build-dependencies]
-bindgen = "^0.72.0"
+# Generally that is 0.72.1 plus some recent changes -- but the one thing that
+# matters over 0.72.1 is that it merges
+# <https://github.com/rust-lang/rust-bindgen/pull/2403> to fix
+# <https://github.com/rust-lang/rust-bindgen/issues/2991>, which affects only
+# native32.
+bindgen = { git = "https://github.com/chrysn-pull-requests/rust-bindgen", branch = "extended-floats"}
 shlex = "^1.3"
 serde_json = "1"
 serde = { version = "1", features = [ "derive" ] }