app/testpmd: compact RSS types output

app/testpmd: compact RSS types output

In port info command output, 'show port info all', supported RSS offload
types printed one type per line, and although this information is not
most important part of the command it takes big part of the command
output.

In port RSS hash and flow RSS command output, 'show port 0 rss-hash',
and 'flow query 0 0 rss', all enabled RSS types are printed on one line.
If there are many types, the print will be very long.

Compacting these RSS offloads and types output by fixing the length of
the character string printed on each line, instead of one per line or
one line.
Output becomes as following:

Supported RSS offload flow types:
  ipv4-frag  ipv4-tcp  ipv4-udp  ipv4-sctp  ipv4-other
  ipv6-frag  ipv6-tcp  ipv6-udp  ipv6-sctp  ipv6-other
  l4-dst-only  l4-src-only  l3-dst-only  l3-src-only

Signed-off-by: Ferruh Yigit <ferruh.yigit@xilinx.com>
Signed-off-by: Huisong Li <lihuisong@huawei.com>