hw/misc/mos6522: Fix bad class definition of the MOS6522 device

hw/misc/mos6522: Fix bad class definition of the MOS6522 device

When compiling QEMU with --enable-cfi, the "q800" m68k machine
currently crashes very early, when the q800_machine_init() function
tries to wire the interrupts of the "via1" device.
This happens because TYPE_MOS6522_Q800_VIA1 is supposed to be a
proper SysBus device, but its parent (TYPE_MOS6522) has a mistake
in its class definition where it is only derived from DeviceClass,
and not from SysBusDeviceClass, so we end up in funny memory access
issues here. Using the right class hierarchy for the MOS6522 device
fixes the problem.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2675
Signed-off-by: Thomas Huth <thuth@redhat.com>
Fixes: 51f233ec92 ("misc: introduce new mos6522 VIA device")
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-ID: <20241114104653.963812-1-thuth@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
(cherry picked from commit c3d7c18b0d616cf7fb3c1f325503e1462307209d)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>