net/ixgbe: fix wrong PBA setting

net/ixgbe: fix wrong PBA setting

The datasheet says, if using MSI-X mode, the PBA support
bit of the GPIE register must be set to 1.
DPDK uses polling mode, we cannot hit this issue in the
scenario DPDK PF + DPDK VF. If we use DPDK PF + kernel VF,
as the kernel driver uses interrpt mode, VF may hit RX hang
after running hours.

Fixes: 00e30184daa0 ("ixgbe: add PF support")
Cc: stable@dpdk.org
Signed-off-by: Wenzhuo Lu <wenzhuo.lu@intel.com>
Acked-by: Wei Dai <wei.dai@intel.com>