Original driver requires users to input "afu_bts" args.
But driver can also work without an explicit "afu_bts" args.
Fixes: 05fa3d4a65 ("bus/ifpga: add Intel FPGA bus library")
Cc: stable@dpdk.org
Signed-off-by: Andy Pei <andy.pei@intel.com>
Acked-by: Rosen Xu <rosen.xu@intel.com>