doc: fix linting command for vcbuild

Currently, `vcbuild` only supports `jslint`. `vcbuild lint` will not
work because there is no `lint` task specified in `vcbuild.bat`. Update
documentation to use `vcbuild jslint` instead.

PR-URL: nodejs#11151
Reviewed-By: Nikolai Vavilov <vvnicholas@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

CONTRIBUTING.md

@@ -182,7 +182,9 @@ Running `make test`/`vcbuild test` will run the linter as well unless one or
 more tests fail.
 
 If you want to run the linter without running tests, use
-`make lint`/`vcbuild lint`.
+`make lint`/`vcbuild jslint`. At this time, only JavaScript linting is
+available on Windows. `make lint` on POSIX will run both JavaScript linting and
+C++ linting.
 
 If you are updating tests and just want to run a single test to check it, you
 can use this syntax to run it exactly as the test harness would: