[NFC] polish colossalai/kernel/cuda_native/csrc/cpu_adam.h code style (#945)

colossalai/kernel/cuda_native/csrc/cpu_adam.h

@@ -90,12 +90,18 @@ union AVX_Data {
                    bool grad_half_precision = false, float loss_scale = -1);
 
 class Adam_Optimizer {
-public:
+ public:
   Adam_Optimizer(float alpha = 1e-3, float betta1 = 0.9, float betta2 = 0.999,
                  float eps = 1e-8, float weight_decay = 0,
                  bool adamw_mode = true)
-      : _alpha(alpha), _betta1(betta1), _betta2(betta2), _eps(eps),
-        _weight_decay(weight_decay), _betta1_t(1.0), _betta2_t(1.0), _step(0),
+      : _alpha(alpha),
+        _betta1(betta1),
+        _betta2(betta2),
+        _eps(eps),
+        _weight_decay(weight_decay),
+        _betta1_t(1.0),
+        _betta2_t(1.0),
+        _step(0),
         _adamw_mode(adamw_mode) {}
   ~Adam_Optimizer() {}
 
@@ -135,7 +141,7 @@ public:
     }
   }
 
-private:
+ private:
   float _alpha;
   float _betta1;
   float _betta2;