aspeed/soc: Add AST2700 support

aspeed/soc: Add AST2700 support

Initial definitions for a simple machine using an AST2700 SOC (Cortex-a35 CPU).

AST2700 SOC and its interrupt controller are too complex to handle
in the common Aspeed SoC framework. We introduce a new ast2700
class with instance_init and realize handlers.

AST2700 is a 64 bits quad core cpus and support 8 watchdog.
Update maximum ASPEED_CPUS_NUM to 4 and ASPEED_WDTS_NUM to 8.
In addition, update AspeedSocState to support scuio, sli, sliio and intc.

Add TYPE_ASPEED27X0_SOC machine type.

The SDMC controller is unlocked at SPL stage.
At present, only supports to emulate booting
start from u-boot stage. Set SDMC controller
unlocked by default.

In INTC, each interrupt of INT 128 to INT 136 combines 32 interrupts.
It connect GICINT IRQ GPIO-OUTPUT pins to GIC device with irq 128 to 136.
And, if a device irq is 128 to 136, its irq GPIO-OUTPUT pin is connected to
GICINT or-gates instead of GIC device.

Signed-off-by: Troy Lee <troy_lee@aspeedtech.com>
Signed-off-by: Jamin Lin <jamin_lin@aspeedtech.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>