[NFC] polish colossalai/kernel/cuda_native/csrc/kernels/include/dropout.h code style (#970)

colossalai/kernel/cuda_native/csrc/kernels/include/dropout.h

@@ -3,12 +3,14 @@
 #include <cuda.h>
 #include <cuda_fp16.h>
 #include <stdio.h>
+
 #include <string>
 
 #include "kernels.h"
 
-template <typename T> class Dropout {
-public:
+template <typename T>
+class Dropout {
+ public:
   struct Config {
     float ratio;
     bool training;
@@ -88,7 +90,7 @@ public:
 
   void SetTrainingMode(bool training) { _config.training = training; }
 
-private:
+ private:
   uint8_t *_mask;
   Config _config;
 };