target/riscv/cpu.c: restrict 'mvendorid' value

We're going to change the handling of mvendorid/marchid/mimpid by the
KVM driver. Since these are always present in all CPUs let's put the
same validation for everyone.

It doesn't make sense to allow 'mvendorid' to be different than it
is already set in named (vendor) CPUs. Generic (dynamic) CPUs can have
any 'mvendorid' they want.

Change 'mvendorid' to be a class property created via
'object_class_property_add', instead of using the DEFINE_PROP_UINT32()
macro. This allow us to define a custom setter for it that will verify,
for named CPUs, if mvendorid is different than it is already set by the
CPU. This is the error thrown for the 'veyron-v1' CPU if 'mvendorid' is
set to an invalid value:

$ qemu-system-riscv64 -M virt -nographic -cpu veyron-v1,mvendorid=2
qemu-system-riscv64: can't apply global veyron-v1-riscv-cpu.mvendorid=2:
    Unable to change veyron-v1-riscv-cpu mvendorid (0x61f)

Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20230706101738.460804-4-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
1 file changed