numa: make "nr_online_nodes" unsigned int

Number of online NUMA nodes can't be negative as well.  This doesn't
save space as the variable is used only in 32-bit context, but do it
anyway for consistency.

Link: http://lkml.kernel.org/r/20190201223151.GB15820@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 8df43ca..c29828e 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -290,7 +290,7 @@ EXPORT_SYMBOL(movable_zone);
 
 #if MAX_NUMNODES > 1
 unsigned int nr_node_ids __read_mostly = MAX_NUMNODES;
-int nr_online_nodes __read_mostly = 1;
+unsigned int nr_online_nodes __read_mostly = 1;
 EXPORT_SYMBOL(nr_node_ids);
 EXPORT_SYMBOL(nr_online_nodes);
 #endif
@@ -5664,7 +5664,7 @@ void __ref build_all_zonelists(pg_data_t *pgdat)
 	else
 		page_group_by_mobility_disabled = 0;
 
-	pr_info("Built %i zonelists, mobility grouping %s.  Total pages: %ld\n",
+	pr_info("Built %u zonelists, mobility grouping %s.  Total pages: %ld\n",
 		nr_online_nodes,
 		page_group_by_mobility_disabled ? "off" : "on",
 		vm_total_pages);