sh: fix size calculation for NUMA node 0

Fix the NUMA size calculation for node 0. Do the same
as the UMA version of setup_memory() and use address
instead of pfn when calculating the size.
Signed-off-by: NMagnus Damm <damm@opensource.se>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/mm/numa.c

@@ -28,7 +28,7 @@ void __init setup_memory(void)
 {
 	unsigned long free_pfn = PFN_UP(__pa(_end));
 	u64 base = min_low_pfn << PAGE_SHIFT;
-	u64 size = (max_low_pfn << PAGE_SHIFT) - min_low_pfn;
+	u64 size = (max_low_pfn << PAGE_SHIFT) - base;
 
 	lmb_add(base, size);