Docs: prebuilt binaries support tile-based output (#4305)

Except when targeting WebAssembly.

docs/api-output.md

@@ -762,10 +762,6 @@ Use a `.zip` or `.szi` file extension with `toFile` to write to a compressed arc
 
 The container will be set to `zip` when the output is a Buffer or Stream, otherwise it will default to `fs`.
 
-Requires libvips compiled with support for libgsf.
-The prebuilt binaries do not include this - see
-[installing a custom libvips](https://sharp.pixelplumbing.com/install#custom-libvips).
-
 
 **Throws**:
 

docs/install.md

@@ -135,6 +135,8 @@ Use in web browsers is unsupported.
 
 Native text rendering is unsupported.
 
+[Tile-based output](/api-output#tile) is unsupported.
+
 ```sh
 npm install --cpu=wasm32 sharp
 ```