net/i40e: fix double flow mark action check

net/i40e: fix double flow mark action check

This commit fixes an issue with the error checking in flow
MARK action. Previously, (ANY + MARK) would fail, as the
(mark_spec == 0) condition would cause an early error return,
however really it is (mark_spec != 0) that should cause the
early error return.

Flipping the binary comparison corrects the behaviour, and
(ANY + MARK) now succeeds, while (MARK + MARK) fails.

Fixes: 0bbcfc706a2b ("net/i40e: support MARK and RSS flow action")

Suggested-by: Harry van Haaren <harry.van.haaren@intel.com>
Signed-off-by: Mesut Ali Ergin <mesut.a.ergin@intel.com>
Acked-by: Qi Zhang <qi.z.zhang@intel.com>