idpf: Fix flow rule delete failure due to invalid validation

idpf: Fix flow rule delete failure due to invalid validation

When deleting a flow rule using "ethtool -N <dev> delete <location>",
idpf_sideband_action_ena() incorrectly validates fsp->ring_cookie even
though ethtool doesn't populate this field for delete operations. The
uninitialized ring_cookie may randomly match RX_CLS_FLOW_DISC or
RX_CLS_FLOW_WAKE, causing validation to fail and preventing legitimate
rule deletions. Remove the unnecessary sideband action enable check and
ring_cookie validation during delete operations since action validation
is not required when removing existing rules.

Fixes: ada3e24b84a0 ("idpf: add flow steering support")
Signed-off-by: Sreedevi Joshi <sreedevi.joshi@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>