Revert "ffmpeg-mux: Disable stdout/stderr on Windows"

This reverts commit 332dd00089cfd86df8e2345d8cd404af36d1981d.

plugins/obs-ffmpeg/ffmpeg-mux/ffmpeg-mux.c

@@ -47,13 +47,6 @@
 
 #define AVIO_BUFFER_SIZE 65536
 
-#if defined(_WIN32) && !defined(ENABLE_FFMPEG_MUX_DEBUG)
-#define fprintf(...)
-#define printf(...)
-#define fflush(x)
-#define puts(x)
-#endif
-
 /* ------------------------------------------------------------------------- */
 
 static char *global_stream_key = "";