ARM: rmobile: Introduce weak default board_init()

Introduce weak default board_init() in rcar-common/common.c , which
allows complete removal of ebisu.c and condor.c at the same time .

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
diff --git a/board/renesas/condor/Makefile b/board/renesas/condor/Makefile
index cf6d566..19e6038 100644
--- a/board/renesas/condor/Makefile
+++ b/board/renesas/condor/Makefile
@@ -9,5 +9,5 @@
 ifdef CONFIG_SPL_BUILD
 obj-y	:= ../rcar-common/gen3-spl.o
 else
-obj-y	:= condor.o ../rcar-common/common.o
+obj-y	:= ../rcar-common/common.o
 endif
diff --git a/board/renesas/condor/condor.c b/board/renesas/condor/condor.c
deleted file mode 100644
index e29c67b..0000000
--- a/board/renesas/condor/condor.c
+++ /dev/null
@@ -1,14 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0+
-/*
- * board/renesas/condor/condor.c
- *     This file is Condor board support.
- *
- * Copyright (C) 2019 Marek Vasut <marek.vasut+renesas@gmail.com>
- */
-
-#include <common.h>
-
-int board_init(void)
-{
-	return 0;
-}
diff --git a/board/renesas/ebisu/Makefile b/board/renesas/ebisu/Makefile
index 1fd9a03..956ce8a 100644
--- a/board/renesas/ebisu/Makefile
+++ b/board/renesas/ebisu/Makefile
@@ -9,5 +9,5 @@
 ifdef CONFIG_SPL_BUILD
 obj-y	:= ../rcar-common/gen3-spl.o
 else
-obj-y	:= ebisu.o ../rcar-common/common.o
+obj-y	:= ../rcar-common/common.o
 endif
diff --git a/board/renesas/ebisu/ebisu.c b/board/renesas/ebisu/ebisu.c
deleted file mode 100644
index 182e980..0000000
--- a/board/renesas/ebisu/ebisu.c
+++ /dev/null
@@ -1,14 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0+
-/*
- * board/renesas/ebisu/ebisu.c
- *     This file is Ebisu board support.
- *
- * Copyright (C) 2018 Marek Vasut <marek.vasut+renesas@gmail.com>
- */
-
-#include <common.h>
-
-int board_init(void)
-{
-	return 0;
-}
diff --git a/board/renesas/rcar-common/common.c b/board/renesas/rcar-common/common.c
index 17940aa..3a0e88b 100644
--- a/board/renesas/rcar-common/common.c
+++ b/board/renesas/rcar-common/common.c
@@ -49,6 +49,11 @@
 	return 0;
 }
 
+int __weak board_init(void)
+{
+	return 0;
+}
+
 #if defined(CONFIG_RCAR_GEN3)
 #define RST_BASE	0xE6160000
 #define RST_CA57RESCNT	(RST_BASE + 0x40)
diff --git a/board/renesas/rcar-common/v3-common.c b/board/renesas/rcar-common/v3-common.c
index be8be0c..7c6202e 100644
--- a/board/renesas/rcar-common/v3-common.c
+++ b/board/renesas/rcar-common/v3-common.c
@@ -39,8 +39,3 @@
 
 	return 0;
 }
-
-int board_init(void)
-{
-	return 0;
-}