Fix clang build (#274)

The attribute is called `optnone`, not `noopt`.

[ROCm/rccl commit: 3899f6e0f2]

projects/rccl/src/init.cc

@@ -125,7 +125,7 @@ ncclResult_t ncclGetUniqueId(ncclUniqueId* out) {
 
 // Prevent compiler from optimizing out these operations
 #ifdef __clang__
-#define NCCL_NO_OPTIMIZE __attribute__((noopt))
+#define NCCL_NO_OPTIMIZE __attribute__((optnone))
 #else
 #define NCCL_NO_OPTIMIZE __attribute__((optimize("O0")))
 #endif