avformat/wtvdec: Don't truncate GUIDs

Each of the 16 bytes of a GUID is written as a two-character
hex value and three hyphens, leading to a length of 35.
GCC 13 emits a -Wformat-truncation= warning because of this.

Reviewed-by: Peter Ross <pross@xvid.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavformat/wtvdec.c

@@ -43,7 +43,7 @@
     "%08"PRIx32"-%04"PRIx16"-%04"PRIx16"-%02x%02x%02x%02x%02x%02x%02x%02x"
 #define ARG_PRETTY_GUID(g) \
     AV_RL32(g),AV_RL16(g+4),AV_RL16(g+6),g[8],g[9],g[10],g[11],g[12],g[13],g[14],g[15]
-#define LEN_PRETTY_GUID 34
+#define LEN_PRETTY_GUID 35
 
 /*
  * File system routines