app/testpmd: fix supported RSS offload display

app/testpmd: fix supported RSS offload display

The rte_eth_dev_info.flow_type_rss_offloads is populated in terms of
RTE_ETH_RSS_* bits. If PMD sets RTE_ETH_RSS_L3_SRC_ONLY to
dev_info->flow_type_rss_offloads. testpmd will display "user defined 63"
when run 'show port info 0'. Because testpmd use flowtype_to_str()
to display the supported RSS offload of PMD. In fact, the function is
used to display flow type in FDIR commands for i40e or ixgbe. This patch
uses the RTE_ETH_RSS_* bits to display supported RSS offload of PMD.

Fixes: b12964f621dc ("ethdev: unification of RSS offload types")
Cc: stable@dpdk.org
Signed-off-by: Huisong Li <lihuisong@huawei.com>
Signed-off-by: Ferruh Yigit <ferruh.yigit@xilinx.com>