!13516 [MSLITE][Develop] fix bug of fp32 grad op: unsorted_segmaent_sum

From: @yangruoqi713
Reviewed-by: @zhang_xue_tong,@hangangqiang
Signed-off-by: @zhang_xue_tong

mindspore/lite/src/runtime/kernel/arm/fp32_grad/unsorted_segment_sum.cc

@@ -38,6 +38,8 @@ int UnsortedSegmentSumCPUKernel::Init() {
   auto input_shape = in_tensors_.at(0)->shape();
   auto segment_ids_shape = in_tensors_.at(1)->shape();
   auto output_shape = out_tensors_.at(0)->shape();
+  unit_num_ = 1;
+  input_dim1_ = 1;
   for (size_t i = 0; i < input_shape.size(); ++i) {
     unit_num_ *= input_shape[i];
     if (i >= segment_ids_shape.size()) {
@@ -45,6 +47,7 @@ int UnsortedSegmentSumCPUKernel::Init() {
     }
   }
   output_dim0_ = output_shape[0];
+  output_dim1_ = 1;
   for (size_t j = 1; j < output_shape.size(); j++) {
     output_dim1_ *= output_shape[j];
   }

mindspore/lite/src/runtime/kernel/arm/fp32_grad/unsorted_segment_sum.h

@@ -32,10 +32,10 @@ class UnsortedSegmentSumCPUKernel : public LiteKernel {
   int ReSize() override;
   int Run() override;
   int Execute(int task_id);
-  size_t unit_num_;
-  size_t input_dim1_;
-  size_t output_dim0_;
-  size_t output_dim1_;
+  size_t unit_num_ = 0;
+  size_t input_dim1_ = 0;
+  size_t output_dim0_ = 0;
+  size_t output_dim1_ = 0;
 
  private:
 };