docs: add internal reference to multi-backend guide (#1352)

Author: Titus-von-Koeller

docs/source/installation.mdx

@@ -137,7 +137,7 @@ export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/home/YOUR_USERNAME/local/cuda-11.7
 ## Multi-backend[[multi-backend]]
 
 > [!TIP]
-> This functionality is currently in preview and therefore not yet production-ready!
+> This functionality is currently in preview and therefore not yet production-ready! Please reference [this guide](./non_cuda_backends) for more in-depth information about the different backends and their current status.
 
 Please follow these steps to install bitsandbytes with device-specific backend support other than CUDA: