ioping: include sys/sysmacros.h for makedev

The makedev prototype is in sys/sysmacros.h, so include it.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

ioping.c

@@ -48,6 +48,7 @@
 #ifdef __linux__
 # include <sys/ioctl.h>
 # include <sys/mount.h>
+# include <sys/sysmacros.h>
 # define HAVE_CLOCK_GETTIME
 # define HAVE_POSIX_FADVICE
 # define HAVE_POSIX_MEMALIGN