The *_lruvec_slab_state is also suitable for pages allocated from buddy,
not just for the slab objects.  But the function name seems to tell us
that only slab object is applicable.  So we can rename the keyword of slab
to kmem.

Link: https://lkml.kernel.org/r/20201117085249.24319-1-songmuchun@bytedance.comSigned-off-by: NMuchun Song <songmuchun@bytedance.com>
Acked-by: NRoman Gushchin <guro@fb.com>
Reviewed-by: NShakeel Butt <shakeelb@google.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>