Fixed some issues found by winapi_check.

diff --git a/msdos/ppdev.c b/msdos/ppdev.c
index b413eb7..e7eec66 100644
--- a/msdos/ppdev.c
+++ b/msdos/ppdev.c
@@ -26,7 +26,9 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
-#include <sys/ioctl.h>
+#ifdef HAVE_SYS_IOCTL_H
+# include <sys/ioctl.h>
+#endif
 #include <errno.h>
 #include <linux/ppdev.h>