board: ti: am64x: Init DRAM size in R5/A53 SPL

Call dram_init_banksize() from spl_board_init() otherwise TFTP download
fails due to lmb_get_free_size() not able to find unreserved region due
to lack of DRAM size info. Required to support Ethernet boot on AM64x.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>

board/ti/am64x/evm.c

@@ -196,5 +196,8 @@ void spl_board_init(void)
 	val = readl(CTRLMMR_USB0_PHY_CTRL);
 	val &= ~(CORE_VOLTAGE);
 	writel(val, CTRLMMR_USB0_PHY_CTRL);
+
+	/* Init DRAM size for R5/A53 SPL */
+	dram_init_banksize();
 }
 #endif