Add link to webgpu node package

Bug: 42240710
Change-Id: I509b1bc8d51f702adc65607802a27cfac6fa44f9
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/248474
Bot-Commit: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Gregg Tavares <gman@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
diff --git a/src/dawn/node/README.md b/src/dawn/node/README.md
index cea704d..bbc30ee 100644
--- a/src/dawn/node/README.md
+++ b/src/dawn/node/README.md
@@ -2,6 +2,13 @@
 
 Note: This code is currently WIP. There are a number of [known issues](#known-issues).
 
+## npm package
+
+There is an npm package named `webgpu` which has dawn.node prebuilt and ready to use.
+See the [npm webgpu](https://www.npmjs.com/package/webgpu). It's build from the
+repo at: https://github.com/dawn-gpu/node-webgpu. See that repo for publishing/updating
+details.
+
 ## Building
 
 ### System requirements