net/ixgbe: fix Rx queue blocking issue
net/ixgbe: fix Rx queue blocking issue

In the IOV scenario, multi Rx queues can be assigned to one VF.
If the dropping is not enabled, when no descriptors are available
for one queue, this queue can block others.

Fixes: 00e30184daa0 ("ixgbe: add PF support")
Cc: stable@dpdk.org

Suggested-by: Liang-Min Larry Wang <2524ccca2a8c3376532a264e722a8ba3ed2154a4@intel.com>
Signed-off-by: Wenzhuo Lu <58cb9036bdff9a5412edc3b9f70e105ccf59954f@intel.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk