Use flow_rule_is_supp_control_flags() to reject filters with
unsupported control flags.

In case any unsupported control flags are masked,
flow_rule_is_supp_control_flags() sets a NL extended
error message, and we return -EOPNOTSUPP.

Only compile-tested.
Signed-off-by: Asbjørn Sloth Tønnesen <ast@fiberby.net>
Reviewed-by: Daniel Machon <daniel.machon@microchip.com>
Tested-by: Daniel Machon <daniel.machon@microchip.com>
Link: https://lore.kernel.org/r/20240424121632.459022-5-ast@fiberby.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>