hw/intc/aspeed: Support different memory region ops

hw/intc/aspeed: Support different memory region ops

The previous implementation set the "aspeed_intc_ops" struct, containing read
and write callbacks, to be used when I/O is performed on the INTC region.
Both "aspeed_intc_read" and "aspeed_intc_write" callback functions were used
for INTC (CPU Die).

To support the INTCIO (IO Die) model, introduces a new "reg_ops" class
attribute. This allows setting different memory region operations to support
different INTC models.

Will introduce "aspeed_intcio_read" and "aspeed_intcio_write" callback
functions are used for INTCIO.

Signed-off-by: Jamin Lin <jamin_lin@aspeedtech.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250307035945.3698802-11-jamin_lin@aspeedtech.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>