The action autocomplete routine (_tc_action_options) currently does not
support several actions statements in one tc command line as it uses the
_tc_once_attr and _tc_one_from_list.
For example, in that case:
$ tc filter add dev eth0 handle ffff: u32 [...] \
action sample group 5 rate 12 \
action sample <TAB>
the _tc_once_attr function, when invoked with "group rate" will not
suggest those as they already exist on the command line.
Fix the function to use the _from variant, thus allowing each action
autocomplete start from the action keyword, and not from the beginning of
the command line.
Signed-off-by: Yotam Gigi <yotamg@mellanox.com>