pdr: pldm_entity_association_pdr_extract(): Hoist assert() over malloc()

The asserted condition was unrelated to the invocation of malloc().
Instead, put it adjacent to the assignment of `*num_entites`, which is
the quantity used to derive the asserted property.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Change-Id: Iadbfe9a68e913fb7e7ea353e4964b9e9bc62fda4
diff --git a/src/pdr.c b/src/pdr.c
index 5713216..aeab9e1 100644
--- a/src/pdr.c
+++ b/src/pdr.c
@@ -1306,11 +1306,11 @@
 		(struct pldm_pdr_entity_association *)start;
 	*num_entities = entity_association_pdr->num_children + 1;
 	assert(*num_entities >= 2);
-	*entities = malloc(sizeof(pldm_entity) * *num_entities);
-	assert(*entities != NULL);
 	assert(start + sizeof(struct pldm_pdr_entity_association) +
 		       sizeof(pldm_entity) * (*num_entities - 2) ==
 	       end);
+	*entities = malloc(sizeof(pldm_entity) * *num_entities);
+	assert(*entities != NULL);
 	(*entities)[0].entity_type =
 		le16toh(entity_association_pdr->container.entity_type);
 	(*entities)[0].entity_instance_num =