generic-board: show model name in board_init_f() too

The common/board_r.c has show_model_r() to display the model name
if the DTB has a "model" property.  It sounds useful to have a similar
function in common/board_f.c too because most of the boards show
their board name before relocation.

Instead of implementing the same function in both common/board_f.c
and common/board_r.c, let's split it up into common/show_board_info.c.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/common/Makefile b/common/Makefile
index 94554f2..9579ab4 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -27,6 +27,8 @@
 # boards
 obj-$(CONFIG_SYS_GENERIC_BOARD) += board_f.o
 obj-$(CONFIG_SYS_GENERIC_BOARD) += board_r.o
+obj-$(CONFIG_DISPLAY_BOARDINFO) += board_info.o
+obj-$(CONFIG_DISPLAY_BOARDINFO_LATE) += board_info.o
 
 # core command
 obj-y += cmd_boot.o