include stdio.h (FreeBSD build fix)

src/file/mmc_device_linux.c

@@ -32,6 +32,7 @@
 #include "util/strutl.h"
 
 #include <stdlib.h>
+#include <stdio.h>
 #include <string.h>
 #include <unistd.h>
 #include <fcntl.h>