Fix libinput mac build, hopefully.

Restore the ifdefs removed in go/ag/12549959, but using
ifdef __linux__ instead of __ANDROID__.

Test: m libinput
Bug: 172023026
Change-Id: Iafbf592e7b937b780e5ffc2df490a6c17f5f6cf5
diff --git a/include/input/Input.h b/include/input/Input.h
index d3a9694..3facfa5 100644
--- a/include/input/Input.h
+++ b/include/input/Input.h
@@ -177,7 +177,9 @@
 
 namespace android {
 
+#ifdef __linux__
 class Parcel;
+#endif
 
 const char* inputEventTypeToString(int32_t type);
 
@@ -344,8 +346,10 @@
         return getAxisValue(AMOTION_EVENT_AXIS_Y);
     }
 
+#ifdef __linux__
     status_t readFromParcel(Parcel* parcel);
     status_t writeToParcel(Parcel* parcel) const;
+#endif
 
     bool operator==(const PointerCoords& other) const;
     inline bool operator!=(const PointerCoords& other) const {
@@ -704,8 +708,10 @@
     // Matrix is in row-major form and compatible with SkMatrix.
     void transform(const std::array<float, 9>& matrix);
 
+#ifdef __linux__
     status_t readFromParcel(Parcel* parcel);
     status_t writeToParcel(Parcel* parcel) const;
+#endif
 
     static bool isTouchEvent(uint32_t source, int32_t action);
     inline bool isTouchEvent() const {