mm/slub: Simplify struct slab slabs field definition

Before commit b47291ef02 ("mm, slub: change percpu partial accounting
from objects to pages") we had to fit two integer fields into a native
word size, so we used short int on 32-bit and int on 64-bit via #ifdef.
After that commit there is only one integer field, so we can simply
define it as int everywhere.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>

mm/slab.h

@@ -27,11 +27,7 @@ struct slab {
 		struct rcu_head rcu_head;
 		struct {
 			struct slab *next;
-#ifdef CONFIG_64BIT
 			int slabs;	/* Nr of slabs left */
-#else
-			short int slabs;
-#endif
 		};
 	};
 	struct kmem_cache *slab_cache;