[Bugfix] DeepGemm utils : Fix hardcoded type-cast (#21517)

Signed-off-by: Varun Sundar Rabindranath <vsundarr@redhat.com>
Co-authored-by: Varun Sundar Rabindranath <vsundarr@redhat.com>

vllm/model_executor/layers/fused_moe/deep_gemm_utils.py

@@ -52,7 +52,7 @@ def compute_aligned_M(M: int, num_topk: int, local_num_experts: int,
 @triton.jit
 def apply_expert_map(expert_id, expert_map):
     if expert_id != -1:
-        expert_id = tl.load(expert_map + expert_id).to(tl.int64)
+        expert_id = tl.load(expert_map + expert_id).to(expert_id.dtype)
     return expert_id