Don't write a NULL terminator at the end of the buffer

* Note: we do write a NULL terminator after the data (even if it's
  truncated) we just don't want to write it at the end of the buffer too

renderdoc/serialise/utf8printf.cpp

@@ -1127,8 +1127,6 @@ int utf8printf(char *buf, size_t bufsize, const char *fmt, va_list args)
   size_t actualsize = 0;
   char *output = buf;
   char *end = buf ? buf + bufsize - 1 : NULL;
-  if(end)
-    *end = 0;
 
   const char *iter = fmt;