lib/coreboot_tables: Remove weak fill_lb_framebuffer()

Remove the weak function stub fill_lb_framebuffer() and guard with the
new `CONFIG_LINEAR_FRAMEBUFFER` instead.

Change-Id: Ia9e477c2d501b249a632968b5636ac803323895a
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/19807
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Philippe Mathieu-Daudé <philippe.mathieu.daude@gmail.com>
diff --git a/src/lib/coreboot_table.c b/src/lib/coreboot_table.c
index f3cdb0b..aa6c7a5 100644
--- a/src/lib/coreboot_table.c
+++ b/src/lib/coreboot_table.c
@@ -135,17 +135,12 @@
 	console->type = consoletype;
 }
 
-int __attribute__((weak)) fill_lb_framebuffer(struct lb_framebuffer *fb)
-{
-	return -1;
-}
-
 static void lb_framebuffer(struct lb_header *header)
 {
 	struct lb_framebuffer *framebuffer;
 	struct lb_framebuffer fb;
 
-	if (fill_lb_framebuffer(&fb))
+	if (!IS_ENABLED(CONFIG_LINEAR_FRAMEBUFFER) || fill_lb_framebuffer(&fb))
 		return;
 
 	framebuffer = (struct lb_framebuffer *)lb_new_record(header);