mctp command: add route range support

[jk-ozlabs]

The MCTP netlink interface allows for a range of EIDs in a route, but the mctp tool has no way to specify a "ranged" route.

Main design component is how the command-line route add interface specifies this. Current route add syntax is:

mctp route add <eid> via <dev> [mtu <mtu>]

And a couple of options:

mctp route add <eid> [to <eid>] via <dev> [mtu <mtu>]

or

mctp route add <eid>[-<eid>] via <dev> [mtu <mtu>]

or any others?

[amboar]

<eid>[-<eid>] IMO

[jk-ozlabs]

@mkj mentions that the to syntax has a different meaning in ip route, so let's discount that and go with <eid>-<eid>.