test-hwc2: Corrected rotation to be clock-wise

Test: Ran on (heavily modified ryu)

Bug: 64723426
Change-Id: I203fb313b6b2c865f6d9a0920a2ffd3714be5e96
diff --git a/services/surfaceflinger/tests/hwc2/Hwc2TestBuffer.cpp b/services/surfaceflinger/tests/hwc2/Hwc2TestBuffer.cpp
index 1d3a1d3..6873c45 100644
--- a/services/surfaceflinger/tests/hwc2/Hwc2TestBuffer.cpp
+++ b/services/surfaceflinger/tests/hwc2/Hwc2TestBuffer.cpp
@@ -570,8 +570,8 @@
                      * (100x50) at the end of the transformation. */
                     if (transform & HWC_TRANSFORM_ROT_90) {
                         float tmp = xPos;
-                        xPos = -yPos * dfW / dfH;
-                        yPos = tmp * dfH / dfW;
+                        xPos = yPos * dfW / dfH;
+                        yPos = -tmp * dfH / dfW;
                     }
 
                     /* Change origin back to the top left corner of the