tools/vm/slabinfo.c: fix sign-compare warning

Currently we get the following compiler warning:

    slabinfo.c:854:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
       if (s->object_size < min_objsize)
                          ^

due to the mismatch of signed/unsigned comparison.  ->object_size and
->slab_size are never expected to be negative, so let's define them as
unsigned int.

[n-horiguchi@ah.jp.nec.com: convert everything - none of these can be negative]
  Link: http://lkml.kernel.org/r/20180826234947.GA9787@hori1.linux.bs1.fc.nec.co.jp
Link: http://lkml.kernel.org/r/1535103134-20239-1-git-send-email-n-horiguchi@ah.jp.nec.com
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tools/vm/slabinfo.c

@@ -30,8 +30,8 @@ struct slabinfo {
 	int alias;
 	int refs;
 	int aliases, align, cache_dma, cpu_slabs, destroy_by_rcu;
-	int hwcache_align, object_size, objs_per_slab;
-	int sanity_checks, slab_size, store_user, trace;
+	unsigned int hwcache_align, object_size, objs_per_slab;
+	unsigned int sanity_checks, slab_size, store_user, trace;
 	int order, poison, reclaim_account, red_zone;
 	unsigned long partial, objects, slabs, objects_partial, objects_total;
 	unsigned long alloc_fastpath, alloc_slowpath;