Minor dlls/wined3d/surface_gdi.c simplification

[Gerald Pfeifer]

ChangeLog:
Remove variable blue_shift which is not really used from 
IWineGDISurfaceImpl_SaveSnapshot.

diff --git a/dlls/wined3d/surface_gdi.c b/dlls/wined3d/surface_gdi.c
index a648cde..d141057 100644
--- a/dlls/wined3d/surface_gdi.c
+++ b/dlls/wined3d/surface_gdi.c
@@ -341,13 +341,12 @@ const char* filename)
             fwrite(output, 3 * This->pow2Width, 1, f);
         }
     } else {
-        int red_shift, green_shift, blue_shift, pix_width, alpha_shift;
+        int red_shift, green_shift, pix_width, alpha_shift;
 
         pix_width = format_desc->byte_count;
 
         red_shift = get_shift(format_desc->red_mask);
         green_shift = get_shift(format_desc->green_mask);
-        blue_shift = get_shift(format_desc->blue_mask);
         alpha_shift = get_shift(format_desc->alpha_mask);
 
         for (y = 0; y < This->pow2Height; y++) {