hw/riscv: virt: Allow support for 32 cores

Linux supports up to 32 cores for both 32-bit and 64-bit RISC-V, so
let's set that as the maximum for the virt board.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/435


Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Message-Id: <20220105213937.1113508-9-alistair.francis@opensource.wdc.com>

include/hw/riscv/virt.h

@@ -24,7 +24,7 @@
 #include "hw/block/flash.h"
 #include "qom/object.h"
 
-#define VIRT_CPUS_MAX 8
+#define VIRT_CPUS_MAX 32
 #define VIRT_SOCKETS_MAX 8
 
 #define TYPE_RISCV_VIRT_MACHINE MACHINE_TYPE_NAME("virt")