net/softnic: fix resource leak for pipeline

net/softnic: fix resource leak for pipeline

For sending request messages to data plane threads, the
caller invokes pipeline_msg_send_recv() function which never
returns null response. Thus, removed redundant check on
the returned response.

Coverity issue: 357676, 357680, 357681, 357682, 357690, 357693, 357711
Coverity issue: 357722, 357725, 357734, 357739, 357743, 357747, 357762
Coverity issue: 357766, 357787

Fixes: 6d4d05402501 ("net/softnic: add command to read stats")
Fixes: 202905f3ee4d ("net/softnic: add command to create objects")
Fixes: ee19326a4b1e ("net/softnic: add command for pipeline table entries")
Fixes: 9bc0ce0ad17c ("net/softnic: add command for meter action")
Fixes: 2505030a8383 ("net/softnic: add command for TTL action")
Cc: stable@dpdk.org
Signed-off-by: Jasvinder Singh <jasvinder.singh@intel.com>
Acked-by: Cristian Dumitrescu <cristian.dumitrescu@intel.com>