sh: Make sure indexes are positive

The indexes are signed, make sure they are not negative
when we read array elements.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/mm/numa.c

@@ -60,7 +60,7 @@ void __init setup_bootmem_node(int nid, unsigned long start, unsigned long end)
 	unsigned long bootmem_paddr;
 
 	/* Don't allow bogus node assignment */
-	BUG_ON(nid > MAX_NUMNODES || nid == 0);
+	BUG_ON(nid > MAX_NUMNODES || nid <= 0);
 
 	start_pfn = start >> PAGE_SHIFT;
 	end_pfn = end >> PAGE_SHIFT;