Move nfs.c:foreach_nfs_shareopt() to libshare.c:foreach_shareopt()
so that it can be (re)used in other parts of libshare.
nfs_disable_share(sa_share_impl_t impl_share)
{
	if (!nfs_available()) {
		/*
		 * The share can't possibly be active, so nothing
		 * needs to be done to disable it.
		 */
		return (SA_OK);
	}

	return (foreach_nfs_host(impl_share, nfs_disable_share_one, NULL));
}

nfs_disable_share(sa_share_impl_t impl_share)
{
	if (!nfs_available()) {
		/*
		 * The share can't possibly be active, so nothing
		 * needs to be done to disable it.
		 */
		return (SA_OK);
	}

	return (foreach_nfs_host(impl_share, nfs_disable_share_one, NULL));
}
