modules/codec/ffmpeg/video.c: Fix Remi Duraffort's PIX_FMT_RGBA issue by...

modules/codec/ffmpeg/video.c: Fix Remi Duraffort's PIX_FMT_RGBA issue by testing directly for PIX_FMT_RGBA definition, instead of testing if swscale is present.

modules/codec/ffmpeg/video.c

@@ -126,7 +126,7 @@ static uint32_t ffmpeg_PixFmtToChroma( int i_ff_chroma )
         return VLC_FOURCC('R','V','2','4');
     case PIX_FMT_RGBA32:
         return VLC_FOURCC('R','V','3','2');
-#if defined(HAVE_FFMPEG_SWSCALE_H) || defined(HAVE_LIBSWSCALE_TREE)
+#ifdef PIX_FMT_RGBA
     case PIX_FMT_RGBA:
         return VLC_FOURCC('R','G','B','A');
 #endif