Migrate run-make/rustdoc-output-path to rmake

Author: GuillaumeGomez

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -246,7 +246,6 @@ run-make/rmeta-preferred/Makefile
 run-make/rustc-macro-dep-files/Makefile
 run-make/rustdoc-io-error/Makefile
 run-make/rustdoc-map-file/Makefile
-run-make/rustdoc-output-path/Makefile
 run-make/rustdoc-scrape-examples-invalid-expr/Makefile
 run-make/rustdoc-scrape-examples-macros/Makefile
 run-make/rustdoc-scrape-examples-multiple/Makefile

tests/run-make/rustdoc-output-path/Makefile

@@ -0,0 +1,9 @@
+// Checks that if the output folder doesn't exist, rustdoc will create it.
+
+use run_make_support::{rustdoc, tmp_dir};
+
+fn main() {
+    let out_dir = tmp_dir().join("foo/bar/doc");
+    rustdoc().input("foo.rs").output(&out_dir).run();
+    assert!(out_dir.exists());
+}