net: sch: api: add extack support in qdisc_alloc

This patch adds extack support for the function qdisc_alloc which is
a common used function in the tc subsystem. Callers which are interested
in the receiving error can assign extack to get a more detailed
information why qdisc_alloc failed.

Cc: David Ahern <[email protected]>
Acked-by: Jamal Hadi Salim <[email protected]>
Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
3 files changed