gdiplus: qualify reference to Gdiplus::Pixelformat

[Iain Arnell]

This patch fixes the remaining bitrot in gdiplus C++ headers by
unambiguously qualifying the reference to Gdiplus::PixelFormat to avoid
"declaration of ... changes meaning of ..." error with GCC 4.3.
---
 include/gdiplusimaging.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/include/gdiplusimaging.h b/include/gdiplusimaging.h
index 42a00cb..7c199c3 100644
--- a/include/gdiplusimaging.h
+++ b/include/gdiplusimaging.h
@@ -110,7 +110,7 @@ public:
     UINT Width;
     UINT Height;
     INT Stride;
-    PixelFormat PixelFormat;
+    Gdiplus::PixelFormat PixelFormat;
     VOID* Scan0;
     UINT_PTR Reserved;
 };
-- 
1.7.3.5