Merge commit 'bf0cef5c'

* commit 'bf0cef5c':
  checkasm: Include io.h for isatty, if available
Merged-by: Michael Niedermayer <michael@niedermayer.cc>

tests/checkasm/checkasm.c

@@ -29,6 +29,10 @@
 #include "libavutil/cpu.h"
 #include "libavutil/random_seed.h"
 
+#if HAVE_IO_H
+#include <io.h>
+#endif
+
 #if ARCH_X86
 #include "libavutil/x86/cpu.h"
 #endif