This reverts commit de9d61e8.

Now 'cpu_clean_all_dirty' is useless, we can revert the related code.

Conflicts:
	include/sysemu/kvm.h

Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1446695464-27116-3-git-send-email-liang.z.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>