[Docs] Make installation URLs nicer (#14556)

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

docs/source/getting_started/installation.md

@@ -0,0 +1,28 @@
+(installation-index)=
+
+# Installation
+
+vLLM supports the following hardware platforms:
+
+:::{toctree}
+:maxdepth: 1
+:hidden:
+
+installation/gpu
+installation/cpu
+installation/ai_accelerator
+:::
+
+- <project:installation/gpu.md>
+  - NVIDIA CUDA
+  - AMD ROCm
+  - Intel XPU
+- <project:installation/cpu.md>
+  - Intel/AMD x86
+  - ARM AArch64
+  - Apple silicon
+- <project:installation/ai_accelerator.md>
+  - Google TPU
+  - Intel Gaudi
+  - AWS Neuron
+  - OpenVINO