zmx25: Remove dram_init_banksize()

As only one RAM bank is used we can rely on the code from arch/arm/lib/board.c

Cc: Matthias Weisser <weisserm@arcor.de>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Stefano Babic <sbabic@denx.de>

board/syteco/zmx25/zmx25.c

@@ -188,9 +188,3 @@ int dram_init(void)
 				PHYS_SDRAM_SIZE);
 	return 0;
 }
-
-void dram_init_banksize(void)
-{
-	gd->bd->bi_dram[0].start = PHYS_SDRAM;
-	gd->bd->bi_dram[0].size = gd->ram_size;
-}