sched: rework configuration failure handling

sched: rework configuration failure handling

Currently, rte_sched_free_memory() is called multiple times by the
exception handling code in rte_sched_subport_config() and
rte_sched_pipe_config().

This patch optimizes them into a unified outlet to free memory.

Fixes: ac6fcb841b0f ("sched: update subport rate dynamically")
Fixes: 34a90f86657c ("sched: modify pipe functions for config flexibility")
Fixes: ce7c4fd7c2ac ("sched: add pipe config to subport level")
Cc: stable@dpdk.org
Signed-off-by: Huisong Li <lihuisong@huawei.com>
Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
Acked-by: Cristian Dumitrescu <cristian.dumitrescu@intel.com>