net: sched: rename QDISC_DROP_FQ_* to generic names

net: sched: rename QDISC_DROP_FQ_* to generic names

Rename FQ-specific drop reasons to generic names:
- QDISC_DROP_FQ_BAND_LIMIT -> QDISC_DROP_BAND_LIMIT
- QDISC_DROP_FQ_HORIZON_LIMIT -> QDISC_DROP_HORIZON_LIMIT

This follows the principle that drop reasons should describe the drop
mechanism rather than being tied to a specific qdisc implementation.
These concepts (priority band limits, timestamp horizon) could apply
to other qdiscs as well.

Remove the local macro define FQDR() and instead use the
full QDISC_DROP_* name to make it easier to navigate code.

Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/177211346902.3011628.12523261489552097455.stgit@firesoul
Signed-off-by: Jakub Kicinski <kuba@kernel.org>