board_f: Drop setup_dram_config() wrapper

By making dram_init_banksize() return an error code we can drop the
wrapper. Adjust this and clean up all implementations.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/board/hisilicon/hikey/hikey.c b/board/hisilicon/hikey/hikey.c
index df3b5e7..0f0eb3a 100644
--- a/board/hisilicon/hikey/hikey.c
+++ b/board/hisilicon/hikey/hikey.c
@@ -410,7 +410,7 @@
 	return 0;
 }
 
-void dram_init_banksize(void)
+int dram_init_banksize(void)
 {
 	/*
 	 * Reserve regions below from DT memory node (which gets generated
@@ -442,6 +442,8 @@
 
 	gd->bd->bi_dram[5].start = 0x22000000;
 	gd->bd->bi_dram[5].size = 0x1c000000;
+
+	return 0;
 }
 
 void reset_cpu(ulong addr)