fix_issue583_Remove unnecessary null pointer checks

cinn/runtime/buffer.cc

@@ -26,7 +26,7 @@ Shape::Shape(const Shape &other) : data_(new value_type[other.ndims()]), ndims_(
 void Shape::Resize(int ndim) {
   CHECK_GT(ndim, 0);
   ndims_ = ndim;
-  data_ = new value_type[ndim];
+  data_  = new value_type[ndim];
 }
 
 Shape::value_type &Shape::operator[](int i) {

cinn/runtime/buffer.h

@@ -73,9 +73,7 @@ class Buffer {
     CHECK(data_) << "alloc buffer failed";
   }
   //! Deallocate the memory in host device.
-  void DeallocHost() {
-    data_ = nullptr;
-  }
+  void DeallocHost() { data_ = nullptr; }
 
   T& operator()(int i0) {
     CHECK_EQ(shape_.ndims(), 1);