the value in a new global intf_mtu for use by the application.
These changes were inspired by the patch provided by Robert Blayzor in
PR 187094, and will allow loader(8) to propagate the value to the kernel
along with the other nfs_diskless parms delivered via environment vars.
identifier to the DHCP server. Now you can check for this string
in your dhcp configuration to decide whether you will hand out a
lease to the client or not.