vgacon, arch/*: remove unused screen_info definitions

A number of architectures either kept the screen_info definition for
historical purposes as it used to be required by the generic VT code, or
they copied it from another architecture in order to build the VGA console
driver in an allmodconfig build. The mips definition is used by some
platforms, but the initialization on jazz is not needed.

Now that vgacon no longer builds on these architectures, remove the
stale definitions and initializations.

Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20231009211845.3136536-5-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/sh/kernel/setup.c

@@ -7,7 +7,6 @@
  *  Copyright (C) 1999  Niibe Yutaka
  *  Copyright (C) 2002 - 2010 Paul Mundt
  */
-#include <linux/screen_info.h>
 #include <linux/ioport.h>
 #include <linux/init.h>
 #include <linux/initrd.h>
@@ -69,10 +68,6 @@ EXPORT_SYMBOL(cpu_data);
 struct sh_machine_vector sh_mv = { .mv_name = "generic", };
 EXPORT_SYMBOL(sh_mv);
 
-#ifdef CONFIG_VT
-struct screen_info screen_info;
-#endif
-
 extern int root_mountflags;
 
 #define RAMDISK_IMAGE_START_MASK	0x07FF