hash: fix lock release on add

hash: fix lock release on add

When adding items to a hash table with multiple threads,
there is an spinlock used to prevent data corruption
(unless Transactional Memory is supported).

If there is a failure, the spinlock should be released,
but there were cases where that was not happening.

Fixes: be856325cba3 ("hash: add scalable multi-writer insertion with Intel TSX")
Cc: stable@dpdk.org
Signed-off-by: Mike Stolarchuk <mike.stolarchuk@bigswitch.com>
Acked-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>