Replace an occurence of -1 by PIX_FMT_NONE, fixes icc warning #188:

enumerated type mixed with another type

Originally committed as revision 19283 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/v210enc.c

@@ -124,6 +124,6 @@ AVCodec v210_encoder = {
     encode_init,
     encode_frame,
     encode_close,
-    .pix_fmts = (enum PixelFormat[]){PIX_FMT_YUV422P16, -1},
+    .pix_fmts = (enum PixelFormat[]){PIX_FMT_YUV422P16, PIX_FMT_NONE},
     .long_name = NULL_IF_CONFIG_SMALL("Uncompressed 4:2:2 10-bit"),
 };