ioctl: Use asm-generic/ioctls.h on m32r (enables termiox)

This patch converts m32r 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 TIOCGRS485 and TIOCGRS485, which are unused by
  any driver available on this architecture.
- The generic version adds support for termiox

Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>