atmel: common: Add function to display via DM_VIDEO's API

Add a function to display the company's logo and board information
via the API from DM_VIDEO. This function can be shared by other
atmel boards, so locate it in board/atmel/common folder.

Signed-off-by: Wenyou Yang <wenyou.yang@microchip.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-at91/include/mach/at91_common.h b/arch/arm/mach-at91/include/mach/at91_common.h
index a95fe41..5416eb4 100644
--- a/arch/arm/mach-at91/include/mach/at91_common.h
+++ b/arch/arm/mach-at91/include/mach/at91_common.h
@@ -37,5 +37,6 @@
 void configure_2nd_sram_as_l2_cache(void);
 
 int at91_set_ethaddr(int offset);
+int at91_video_show_board_info(void);
 
 #endif /* AT91_COMMON_H */