tty: vt: use _IO() to define ioctl numbers

tty: vt: use _IO() to define ioctl numbers

_IO*() is the proper way of defining ioctl numbers. All these vt numbers
were synthetically built up the same way the _IO() macro does.

So instead of implicit hex numbers, use _IO() properly.

To not change the pre-existing numbers, use only _IO() (and not _IOR()
or _IOW()). The latter would change the numbers indeed.

Objdump of vt_ioctl.o reveals no difference with this patch.

Again, VT_GETCONSIZECSRPOS already uses _IOR(), so everything is paved
for this patch.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Nicolas Pitre <nico@fluxnic.net>
Reviewed-by: Nicolas Pitre <npitre@baylibre.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20250611100319.186924-8-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>