hw/arm/aspeed: Wire up PCIe devices in SoC model

hw/arm/aspeed: Wire up PCIe devices in SoC model

Add PCIe controller and PHY instances to the Aspeed SoC state and device
enum. This prepares the SoC model to host PCIe Root Complexes and their
associated PHYs.

Although the AST2600 supports only a single Root Complex, the AST2700
provides three Root Complexes. For this reason, the model defines arrays
of three PCIe config/PHY objects and enumerates three PCIe device IDs so
that both SoCs can be represented consistently.

Signed-off-by: Jamin Lin <jamin_lin@aspeedtech.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250919093017.338309-8-jamin_lin@aspeedtech.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>