[Docs] Remove in-tree Gaudi install instructions (vllm-project#23628)

Signed-off-by: Harry Mellor <[email protected]>

Author: hmellor

docs/getting_started/installation/README.md

@@ -12,7 +12,6 @@ vLLM supports the following hardware platforms:
     - [Apple silicon](cpu.md#apple-silicon)
     - [IBM Z (S390X)](cpu.md#ibm-z-s390x)
 - [Google TPU](google_tpu.md)
-- [Intel Gaudi](intel_gaudi.md)
 - [AWS Neuron](aws_neuron.md)
 
 ## Hardware Plugins