pdump library now uses generic multi process channel
and it is no more dependent on the pthreads, so remove
the dependency from the Makefile.
Fixes: 660098d61f57 ("pdump: use generic multi-process channel")
Cc: stable@dpdk.org
Signed-off-by: Reshma Pattan <reshma.pattan@intel.com>
2c6c3e0dc8