fix case of included files

Cross-compiling for mingw requires lowercase filenames.

Change-Id: I135deca455ca2ff6bb3969aca990fe9d1c2dd345
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>
Reviewed-by: Mark Brand <mabrand@mabrand.nl>

src/plugins/common/evr/evrdefs.h

@@ -35,12 +35,12 @@
 #define EVRDEFS_H
 
 #include <d3d9.h>
-#include <Evr9.h>
+#include <evr9.h>
 #include <evr.h>
 #include <dxva2api.h>
 #include <mfapi.h>
 #include <mfidl.h>
-#include <Mferror.h>
+#include <mferror.h>
 
 extern const CLSID clsid_EnhancedVideoRenderer;
 extern const GUID mr_VIDEO_RENDER_SERVICE;