SurfaceControl: Correct setMatrix parameter naming.

The first parameter dsdx controls the X scaling. The last parameter
is called dtdy but controls the Y scaling. Clearly this was meant to be
named dsdy. You can verify this with a quick look at Transaction_test.

Test: Tried various stuff, phone still works.
Change-Id: Ie9e898443350ffdcf227888a8d85efdbe1b6b033
diff --git a/include/private/gui/LayerState.h b/include/private/gui/LayerState.h
index 2a1801b..0bcff46 100644
--- a/include/private/gui/LayerState.h
+++ b/include/private/gui/LayerState.h
@@ -77,8 +77,8 @@
             struct matrix22_t {
                 float   dsdx{0};
                 float   dtdx{0};
-                float   dsdy{0};
                 float   dtdy{0};
+                float   dsdy{0};
             };
             sp<IBinder>     surface;
             uint32_t        what;