kernel/modules: relocate teql hotplug from iproute2 to kmod-sched

kernel/modules: relocate teql hotplug from iproute2 to kmod-sched

The link equalizer sch_teql.ko of package kmod-sched relies on a hotplug
script historically included in iproute2's tc package. In previous
discussion [1], consensus was the hotplug script is best located together
with the module in kmod-sched, but this change was deferred at the time.

Relocate the hotplug script now. This change also simplifies adding a tc
variant for minimal size with reduced functionality.

[1] https://github.com/openwrt/openwrt/pull/1627#issuecomment-447923636

Signed-off-by: Tony Ambardar <itugrok@yahoo.com>
(cherry picked from commit 863ce4f15f74a674f01ab47f445b362c113b113b)