net: ngbe: specify IRQ vector when the number of VFs is 7

net: ngbe: specify IRQ vector when the number of VFs is 7

For NGBE devices, the queue number is limited to be 1 when SRIOV is
enabled. In this case, IRQ vector[0] is used for MISC and vector[1] is
used for queue, based on the previous patches. But for the hardware
design, the IRQ vector[1] must be allocated for use by the VF[6] when
the number of VFs is 7. So the IRQ vector[0] should be shared for PF
MISC and QUEUE interrupts.

+-----------+----------------------+
| Vector    | Assigned To          |
+-----------+----------------------+
| Vector 0  | PF MISC and QUEUE    |
| Vector 1  | VF 6                 |
| Vector 2  | VF 5                 |
| Vector 3  | VF 4                 |
| Vector 4  | VF 3                 |
| Vector 5  | VF 2                 |
| Vector 6  | VF 1                 |
| Vector 7  | VF 0                 |
+-----------+----------------------+

Minimize code modifications, only adjust the IRQ vector number for this
case.

Fixes: 877253d2cbf2 ("net: ngbe: add sriov function support")
Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com>
Link: https://patch.msgid.link/20250701063030.59340-4-jiawenwu@trustnetic.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>