Make GrSamplerState.h and GrRenderTarget.h private

Change-Id: Id7a270f5a528e1a4a6d94474fa092545252753b3
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/234667
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
diff --git a/src/gpu/GrRenderTarget.cpp b/src/gpu/GrRenderTarget.cpp
index 62935d3..2942427 100644
--- a/src/gpu/GrRenderTarget.cpp
+++ b/src/gpu/GrRenderTarget.cpp
@@ -6,7 +6,7 @@
  */
 
 
-#include "include/gpu/GrRenderTarget.h"
+#include "src/gpu/GrRenderTarget.h"
 
 #include "include/gpu/GrContext.h"
 #include "src/core/SkRectPriv.h"