Sets the size (MB) for PCMCIA disk0.

        :param disk0: disk0 size (integer)

def set_disk0(self, disk0):
        """
        Sets the size (MB) for PCMCIA disk0.

        :param disk0: disk0 size (integer)
        """

        yield from self._hypervisor.send('vm set_disk0 "{name}" {disk0}'.format(name=self._name, disk0=disk0))

        log.info('Router "{name}" [{id}]: disk0 updated from {old_disk0}MB to {new_disk0}MB'.format(name=self._name,
                                                                                                    id=self._id,
                                                                                                    old_disk0=self._disk0,
                                                                                                    new_disk0=disk0))
        self._disk0 = disk0