Fix doc links

Author: gmorenz

src/cargo/core/compiler/unit.rs

@@ -68,7 +68,8 @@ pub struct UnitInner {
     /// As of now, these flags come from environment variables and configurations.
     /// See [`TargetInfo.rustflags`] for more on how Cargo collects them.
     ///
-    /// [`TargetInfo.rustflags`]: TargetInfo::rustflags
+    /// [`BuildContext::extra_args_for`]: crate::core::compiler::build_context::BuildContext::extra_args_for
+    /// [`TargetInfo.rustflags`]: crate::core::compiler::build_context::TargetInfo::rustflags
     pub rustflags: Arc<[String]>,
     /// Extra compiler flags to pass to `rustdoc` for a given unit.
     ///
@@ -78,7 +79,8 @@ pub struct UnitInner {
     /// As of now, these flags come from environment variables and configurations.
     /// See [`TargetInfo.rustdocflags`] for more on how Cargo collects them.
     ///
-    /// [`TargetInfo.rustdocflags`]: TargetInfo::rustdocflags
+    /// [`BuildContext::extra_args_for`]: crate::core::compiler::build_context::BuildContext::extra_args_for
+    /// [`TargetInfo.rustdocflags`]: crate::core::compiler::build_context::TargetInfo::rustdocflags
     pub rustdocflags: Arc<[String]>,
     // if `true`, the dependency is an artifact dependency, requiring special handling when
     // calculating output directories, linkage and environment variables provided to builds.