Remove __restrict__ extension to fix compilation error on GB200 (#1470)

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Fixes the issue in
#1468.

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Author: 842974287

include/flashinfer/comm/vllm_custom_all_reduce.cuh

@@ -58,7 +58,7 @@ struct Signal {
 };
 
 struct __align__(16) RankData {
-  void* __restrict__ ptrs[8];
+  void* ptrs[8];
 };
 
 struct __align__(16) RankSignals {