Revert "InputDevice: return std::optional from getAbsoluteAxisInfo"

This reverts commit 67e1ae63301dc02f4d940b5f480b1f495b3b977e.

Reason for revert: b/353921348

Change-Id: I6148dec70b7ca1c9a21d841b791168b5bfc67ca3
diff --git a/services/inputflinger/reader/include/EventHub.h b/services/inputflinger/reader/include/EventHub.h
index c647558..2a43466 100644
--- a/services/inputflinger/reader/include/EventHub.h
+++ b/services/inputflinger/reader/include/EventHub.h
@@ -71,14 +71,18 @@
 
 /* Describes an absolute axis. */
 struct RawAbsoluteAxisInfo {
+    bool valid{false}; // true if the information is valid, false otherwise
+
     int32_t minValue{};   // minimum value
     int32_t maxValue{};   // maximum value
     int32_t flat{};       // center flat position, eg. flat == 8 means center is between -8 and 8
     int32_t fuzz{};       // error tolerance, eg. fuzz == 4 means value is +/- 4 due to noise
     int32_t resolution{}; // resolution in units per mm or radians per mm
+
+    inline void clear() { *this = RawAbsoluteAxisInfo(); }
 };
 
-std::ostream& operator<<(std::ostream& out, const std::optional<RawAbsoluteAxisInfo>& info);
+std::ostream& operator<<(std::ostream& out, const RawAbsoluteAxisInfo& info);
 
 /*
  * Input device classes.