Add a QOM function hook for target-specific disassembly setup. This
allows removal of the #ifdeffery currently implementing target specific
disas setup from disas.c.
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NPeter Crosthwaite <crosthwaite.peter@gmail.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>