i40e: Store the irq number in i40e_q_vector

[ Upstream commit 6b85a4f3

 ]

Make it easy to figure out the IRQ number for a particular i40e_q_vector by
storing the assigned IRQ in the structure itself.

Signed-off-by: Joe Damato <jdamato@fastly.com>
Acked-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Acked-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Tested-by: Gurucharan <gurucharanx.g@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Stable-dep-of: ea558de7

 ("i40e: Enforce software interrupt during busy-poll exit")
Signed-off-by: Sasha Levin <sashal@kernel.org>