Fix generated constants: `f64::INFINITY`, `f64::NEG_ INFINITY`, `f64::NAN`

https://github.com/rust-lang/rust-bindgen/issues/2853
diff --git a/bindgen/codegen/helpers.rs b/bindgen/codegen/helpers.rs
index bfe1e3d..77a2261 100644
--- a/bindgen/codegen/helpers.rs
+++ b/bindgen/codegen/helpers.rs
@@ -339,7 +339,7 @@
                         ::#prefix::f64::INFINITY
                     }
                 }
-            } else { // sign_negative
+            } else {
                 if rust_target >= RustTarget::Stable_1_43 {
                     quote! {
                         f64::NEG_INFINITY