Changed PROMISE hint for softmax operation to CUDNN hint for lenet_promise.cpp

llvm/test/VISC/DNN_Benchmarks/benchmarks/lenet/src/lenet_promise.cpp

@@ -138,7 +138,7 @@ void var_15_node(void* t1, size_t bytes_t1) {
 }
 
 void var_16_node(void* t1, size_t bytes_t1) { 
-  __visc__hint(visc::PROMISE_TARGET); 
+  __visc__hint(visc::CUDNN_TARGET); 
   __visc__attributes(1, t1, 0); 
 
   void* r = __visc__tensor_softmax(t1);