microblaze: Fix paging init-zone initialization

This patch fix problem with bad zone initialization.
This bug wasn't perform because Microblaze doesn't
define CONFIG_ZONE_DMA and ZONE_NORMAL was 0 for this case
that's why free_area_init works with correct values.

Original message:
I believe that the switch from ZONE_DMA (== 0) to ZONE_NORMAL
broke the free area initialization.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>

arch/microblaze/mm/init.c

@@ -44,16 +44,15 @@ static void __init paging_init(void)
 	int i;
 	unsigned long zones_size[MAX_NR_ZONES];
 
+	/* Clean every zones */
+	memset(zones_size, 0, sizeof(zones_size));
+
 	/*
 	 * old: we can DMA to/from any address.put all page into ZONE_DMA
 	 * We use only ZONE_NORMAL
 	 */
 	zones_size[ZONE_NORMAL] = max_mapnr;
 
-	/* every other zones are empty */
-	for (i = 1; i < MAX_NR_ZONES; i++)
-		zones_size[i] = 0;
-
 	free_area_init(zones_size);
 }