Explain the dockerfile arch handling (#1545)

* Update configuration.md

* Update docs/add-ons/configuration.md

Co-authored-by: Stefan Agner <[email protected]>

Co-authored-by: Stefan Agner <[email protected]>

Author: pvizeli

docs/add-ons/configuration.md

@@ -82,7 +82,7 @@ LABEL \
   io.hass.arch="armhf|aarch64|i386|amd64"
 ```
 
-It is possible to use your own base image with `build.yaml` or if you do not need support for automatic multi-arch building you can also use a simple docker `FROM`.
+It is possible to use your own base image with `build.yaml` or if you do not need support for automatic multi-arch building you can also use a simple docker `FROM`. You can also suffix the Dockerfile with the specific architecture to use a specific Dockerfile for a particular architecture, i.e. `Dockerfile.amd64`.
 
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