[Bug Fix] Fix the support check for FP8 CUTLASS (#5352)

Bug description:
With torch 2.4.0.dev20240603+cu121,
cutlass_fp8_supported outputs False, and the (capability, version) before the comparison is (90, 11111111112)

This PR fixes the support check for FP8 CUTLASS ( cutlass_fp8_supported) which was introduced in https://github.com/vllm-project/vllm/pull/5183.

vllm/model_executor/layers/quantization/fp8.py

@@ -20,16 +20,16 @@ logger = init_logger(__name__)
 def cutlass_fp8_supported() -> bool:
     capability = torch.cuda.get_device_capability()
     capability = capability[0] * 10 + capability[1]
-    version = torch.version.cuda
-    version = version[0] * 10 + version[1]
+    major, minor = torch.version.cuda.split(".")
+    version = int(major) * 10 + int(minor)
 
     # CUTLASS FP8 kernels need at least
     #   CUDA 12.0 on SM90 systems (Hopper)
     #   CUDA 12.4 on SM89 systems (Lovelace)
     gpu_is_supported = False
-    if capability >= 900:
+    if capability >= 90:
         gpu_is_supported = version > 120
-    elif capability >= 890:
+    elif capability >= 89:
         gpu_is_supported = version > 124
 
     return gpu_is_supported