Use struct-like syntax in tool_extended!

Using struct-like syntax allows rustfmt to format macro invocations, instead of
giving up and ignoring them.

Using a separate macro invocation per tool makes the macro slightly simpler,
and isolates syntax errors to individual invocations.

Author: Zalathar

src/bootstrap/src/core/build_steps/tool.rs

@@ -1008,14 +1008,15 @@ impl Step for LibcxxVersionTool {
 
 macro_rules! tool_extended {
     (
-       $($name:ident,
-       $path:expr,
-       $tool_name:expr,
-       stable = $stable:expr
-       $(,add_bins_to_sysroot = $add_bins_to_sysroot:expr)?
-       ;)+) => {
-        $(
-            #[derive(Debug, Clone, Hash, PartialEq, Eq)]
+        $name:ident {
+            path: $path:expr,
+            tool_name: $tool_name:expr,
+            stable: $stable:expr
+            $( , add_bins_to_sysroot: $add_bins_to_sysroot:expr )?
+            $( , )?
+        }
+    ) => {
+        #[derive(Debug, Clone, Hash, PartialEq, Eq)]
         pub struct $name {
             pub compiler: Compiler,
             pub target: TargetSelection,
@@ -1063,7 +1064,6 @@ macro_rules! tool_extended {
                 )
             }
         }
-        )+
     }
 }
 
@@ -1109,15 +1109,33 @@ fn run_tool_build_step(
     }
 }
 
-tool_extended!(
-    Cargofmt, "src/tools/rustfmt", "cargo-fmt", stable=true;
-    CargoClippy, "src/tools/clippy", "cargo-clippy", stable=true;
-    Clippy, "src/tools/clippy", "clippy-driver", stable=true, add_bins_to_sysroot = ["clippy-driver", "cargo-clippy"];
-    Miri, "src/tools/miri", "miri", stable=false, add_bins_to_sysroot = ["miri"];
-    CargoMiri, "src/tools/miri/cargo-miri", "cargo-miri", stable=false, add_bins_to_sysroot = ["cargo-miri"];
-    Rls, "src/tools/rls", "rls", stable=true;
-    Rustfmt, "src/tools/rustfmt", "rustfmt", stable=true, add_bins_to_sysroot = ["rustfmt", "cargo-fmt"];
-);
+tool_extended!(Cargofmt { path: "src/tools/rustfmt", tool_name: "cargo-fmt", stable: true });
+tool_extended!(CargoClippy { path: "src/tools/clippy", tool_name: "cargo-clippy", stable: true });
+tool_extended!(Clippy {
+    path: "src/tools/clippy",
+    tool_name: "clippy-driver",
+    stable: true,
+    add_bins_to_sysroot: ["clippy-driver", "cargo-clippy"]
+});
+tool_extended!(Miri {
+    path: "src/tools/miri",
+    tool_name: "miri",
+    stable: false,
+    add_bins_to_sysroot: ["miri"]
+});
+tool_extended!(CargoMiri {
+    path: "src/tools/miri/cargo-miri",
+    tool_name: "cargo-miri",
+    stable: false,
+    add_bins_to_sysroot: ["cargo-miri"]
+});
+tool_extended!(Rls { path: "src/tools/rls", tool_name: "rls", stable: true });
+tool_extended!(Rustfmt {
+    path: "src/tools/rustfmt",
+    tool_name: "rustfmt",
+    stable: true,
+    add_bins_to_sysroot: ["rustfmt", "cargo-fmt"]
+});
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct TestFloatParse {