ioctl: Use asm-generic/ioctls.h on ia64 (enables termiox)

This patch converts ia64 to use asm-generic/ioctls.h instead of its
own version.

The differences between the arch-specific version and the generic
version are as follows:

- The generic version adds TIOCSRS485 and TIOCGRS485, which are unused
  by any driver available on this architecture.
- The generic version adds support for termiox

Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>