It's possible that we fail to get the IOMMU group of ifcvf device, this
patch adds a check on the return value.
Coverity issue: 349894
Fixes: a3f8150eac6d ("net/ifcvf: add ifcvf vDPA driver")
Cc: stable@dpdk.org
Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
Reviewed-by: Xiaolong Ye <xiaolong.ye@intel.com>
ac466a1d6c