emulator_cmpxchg_emulated writes to guest memory, therefore it should
update the dirty bitmap accordingly.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Reviewed-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>