fix: compilation error on mobile phone

Author: jcs090218

Assets/JCSUnity/Scripts/Interactive/2D/Camera/JCS_2DCamera.cs

@@ -189,8 +189,8 @@ protected virtual void FixedUpdate()
                 // to here...
                 mWheelDegree = Input.GetAxis("Mouse ScrollWheel");
 #elif (UNITY_ANDROID || UNITY_IPHIONE || UNITY_IOS)
-                var slideInput = JCS_TouchInput.FirstInstance();
-                mWheelDegree = slideInput.TouchDistanceDelta;
+                var input = JCS_TouchInput.FirstInstance();
+                mWheelDegree = input.touchDistanceDelta;
 #endif
                 ZoomCamera(mWheelDegree);
             }

Assets/JCSUnity/Scripts/Interactive/3D/JCS_3DCamera.cs

@@ -226,8 +226,8 @@ protected override void LateUpdate()
                 // to here...
                 mWheelDegree = Input.GetAxis("Mouse ScrollWheel");
 #elif (UNITY_ANDROID || UNITY_IPHIONE || UNITY_IOS)
-                var slideInput = JCS_TouchInput.FirstInstance();
-                mWheelDegree = slideInput.TouchDistanceDelta;
+                var input = JCS_TouchInput.FirstInstance();
+                mWheelDegree = input.touchDistanceDelta;
 #endif
                 ZoomCamera(mWheelDegree);
             }