configure: improve check for POSIX ioctl
Instead of relying on system #ifdefs which may or may not be correct,
detect the POSIX ioctl signature at configure time.
(cherry picked from commit 00b64fca55a3a009c9d0e391c85f4fd3291e5d12)
Signed-off-by:
Brad Smith <brad@comstyle.com>