target/riscv: update multi-letter extension KVM properties

target/riscv: update multi-letter extension KVM properties

We're now ready to update the multi-letter extensions status for KVM.

kvm_riscv_update_cpu_cfg_isa_ext() is called called during vcpu creation
time to verify which user options changes host defaults (via the 'user_set'
flag) and tries to write them back to KVM.

Failure to commit a change to KVM is only ignored in case KVM doesn't
know about the extension (-EINVAL error code) and the user wanted to
disable the given extension. Otherwise we're going to abort the boot
process.

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: <20230706101738.460804-19-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>