DAOS-16713 vos: initialize checkpoint stats (#15454)

Initialize checkpoint stats to zero.

Signed-off-by: Niu Yawei <yawei.niu@intel.com>

src/include/daos/mem.h

@@ -289,14 +289,12 @@ struct umem_cache {
 };
 
 struct umem_cache_chkpt_stats {
-	/** Last committed checkpoint id */
-	uint64_t *uccs_chkpt_id;
 	/** Number of pages processed */
-	int       uccs_nr_pages;
+	unsigned int       uccs_nr_pages;
 	/** Number of dirty chunks copied */
-	int       uccs_nr_dchunks;
+	unsigned int       uccs_nr_dchunks;
 	/** Number of sgl iovs used to copy dirty chunks */
-	int       uccs_nr_iovs;
+	unsigned int       uccs_nr_iovs;
 };
 
 /** Allocate global cache for umem store.

src/vos/vos_pool.c

@@ -724,7 +724,7 @@ vos_pool_checkpoint(daos_handle_t poh)
 	struct bio_wal_info            wal_info;
 	int                            rc;
 	uint64_t                       purge_size = 0;
-	struct umem_cache_chkpt_stats  stats;
+	struct umem_cache_chkpt_stats  stats = { 0 };
 	struct vos_chkpt_metrics      *chkpt_metrics = NULL;
 
 	pool = vos_hdl2pool(poh);