spl: add a generic function board_init_f

This commit add a generic function board_init_f that
only initialize some device (for example serial). It
avoid to define a board function only to launch the
serial configuration.

Signed-off-by: Philippe Reynes <philippe.reynes@softathome.com>
diff --git a/common/spl/spl.c b/common/spl/spl.c
index 5fdd6d0..a9d3e84 100644
--- a/common/spl/spl.c
+++ b/common/spl/spl.c
@@ -555,6 +555,24 @@
 	return -ENODEV;
 }
 
+#if defined(CONFIG_SPL_FRAMEWORK_BOARD_INIT_F)
+void board_init_f(ulong dummy)
+{
+	if (CONFIG_IS_ENABLED(OF_CONTROL)) {
+		int ret;
+
+		ret = spl_early_init();
+		if (ret) {
+			debug("spl_early_init() failed: %d\n", ret);
+			hang();
+		}
+	}
+
+	if (CONFIG_IS_ENABLED(SERIAL_SUPPORT))
+		preloader_console_init();
+}
+#endif
+
 void board_init_r(gd_t *dummy1, ulong dummy2)
 {
 	u32 spl_boot_list[] = {