arm64: renesas: Drop unused code and clean up headers on ULCB boards

CONFIG_IS_ENABLED(SYS_I2C_LEGACY) is not set on this board,
remove the code and also remove all unnecessary headers that
are included in this file.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
diff --git a/board/renesas/ulcb/ulcb.c b/board/renesas/ulcb/ulcb.c
index 64f01b1..3f6db0e 100644
--- a/board/renesas/ulcb/ulcb.c
+++ b/board/renesas/ulcb/ulcb.c
@@ -6,37 +6,15 @@
  * Copyright (C) 2017 Renesas Electronics Corporation
  */
 
-#include <image.h>
-#include <init.h>
-#include <malloc.h>
-#include <netdev.h>
-#include <dm.h>
-#include <asm/global_data.h>
-#include <dm/platform_data/serial_sh.h>
-#include <asm/processor.h>
-#include <asm/mach-types.h>
 #include <asm/io.h>
-#include <linux/bitops.h>
-#include <linux/errno.h>
-#include <asm/arch/sys_proto.h>
-#include <asm/gpio.h>
-#include <asm/arch/gpio.h>
-#include <asm/arch/renesas.h>
 #include <asm/arch/rcar-mstp.h>
-#include <i2c.h>
-#include <mmc.h>
-
-DECLARE_GLOBAL_DATA_PTR;
+#include <asm/arch/renesas.h>
+#include <init.h>
 
-#define DVFS_MSTP926		BIT(26)
 #define HSUSB_MSTP704		BIT(4)	/* HSUSB */
 
 int board_early_init_f(void)
 {
-#if CONFIG_IS_ENABLED(SYS_I2C_LEGACY) && defined(CONFIG_SYS_I2C_SH)
-	/* DVFS for reset */
-	mstp_clrbits_le32(SMSTPCR9, SMSTPCR9, DVFS_MSTP926);
-#endif
 	return 0;
 }