Add getRawWidth() and getRawHeight()

Minor refactor to move the computation of raw width and raw height into
RawPointerAxes. This is needed because a future CL will use these
functions again.

Bug: 116239493
Test: atest inputflinger_tests
Change-Id: I25086f9ba370f9891851e87a2b2375af867409f3
diff --git a/services/inputflinger/InputReader.h b/services/inputflinger/InputReader.h
index 3410bc9..9b0007a 100644
--- a/services/inputflinger/InputReader.h
+++ b/services/inputflinger/InputReader.h
@@ -772,6 +772,8 @@
     RawAbsoluteAxisInfo slot;
 
     RawPointerAxes();
+    inline int32_t getRawWidth() const { return x.maxValue - x.minValue + 1; }
+    inline int32_t getRawHeight() const { return y.maxValue - y.minValue + 1; }
     void clear();
 };