video, da8xx-fb: show fb addr in bdinfo

without this patch the bdinfo command shows:
U-Boot# bd
arch_number = 0x000010DC
[...]
sp start    = 0x8EF32F20
FB base     = 0x00000000

with this patch it shows the address where the framebuffer
for this video driver start:

arch_number = 0x000010DC
[...]
sp start    = 0x8EF32F20
FB base     = 0x8EF3C788
Signed-off-by: NHeiko Schocher <hs@denx.de>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Tom Rini <trini@ti.com>
Acked-by: NTom Rini <trini@ti.com>

drivers/video/da8xx-fb.c

@@ -959,6 +959,7 @@ void *video_hw_init(void)
 		printf("GLCD: malloc for frame buffer failed\n");
 		goto err_release_fb;
 	}
+	gd->fb_base = (int)par->vram_virt;
 
 	gpanel.frameAdrs = (unsigned int)par->vram_virt;
 	da8xx_fb_info->screen_base = (char *) par->vram_virt;