Allocate requests for management path separately

Management path does not benefit much from mpools, as number of requests
allocated is very small. It's less restrictive (mngt_queue does not have
single-CPU affinity) thus avoiding mpool usage in management path allows
to introduce additional restrictions on mpool, leading to I/O performance
improvement.

Signed-off-by: Robert Baldyga <robert.baldyga@huawei.com>
Signed-off-by: Michal Mielewczyk <michal.mielewczyk@huawei.com>

src/mngt/ocf_mngt_flush.c

@@ -432,7 +432,7 @@ static void _ocf_mngt_flush_container(
 	fc->end = end;
 	fc->context = context;
 
-	req = ocf_req_new(cache->mngt_queue, NULL, 0, 0, 0);
+	req = ocf_req_new_mngt(cache->mngt_queue);
 	if (!req) {
 		error = OCF_ERR_NO_MEM;
 		goto finish;