SF: Rename VsyncModulator

Adopt Vsync/vsync spelling over the awkward and less common VSync/vSync.

Bug: 160012986
Test: Build
Change-Id: Ibe230906e969d2ef8100ca7b1f5650dfe227c927
diff --git a/services/surfaceflinger/Android.bp b/services/surfaceflinger/Android.bp
index c55e9df..e452187 100644
--- a/services/surfaceflinger/Android.bp
+++ b/services/surfaceflinger/Android.bp
@@ -176,7 +176,7 @@
         "Scheduler/Timer.cpp",
         "Scheduler/VSyncDispatchTimerQueue.cpp",
         "Scheduler/VSyncPredictor.cpp",
-        "Scheduler/VSyncModulator.cpp",
+        "Scheduler/VsyncModulator.cpp",
         "Scheduler/VSyncReactor.cpp",
         "StartPropertySetThread.cpp",
         "SurfaceFlinger.cpp",