LoongArch: KVM: Add mmio trace events support

Add mmio trace events support, currently generic mmio events
KVM_TRACE_MMIO_WRITE/xxx_READ/xx_READ_UNSATISFIED are added here.

Also vcpu id field is added for all kvm trace events, since perf
KVM tool parses vcpu id information for kvm entry event.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>