ioctl_list.2: Remove this page

ioctl_list.2: Remove this page

This page was first added more than 20 years ago. Since
that time it has seen hardly any update, and is by now
very much out of date, as reported by Heinrich Schuchardt
and confirmed by Eugene Syromyatnikov.

As Heinrich says:

    Man-pages like netdevices.7 or ioctl_fat.2 are what is
    needed to help a user who does not want to read through the
    kernel code.

    If ioctl_list.2 has not been reasonably maintained since
    Linux 1.3.27 and hence is not a reliable source of
    information, shouldn't it be dropped?

My answer is, yes (but let's move a little info into ioctl(2)).

Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reported-by: Eugene Syromyatnikov <evgsyr@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>