Basic braille screen reader support

This adds a minimalistic braille screen reader support.  This is meant to
be used by blind people e.g.  on boot failures or when / cannot be mounted
etc and thus the userland screen readers can not work.

[akpm@linux-foundation.org: fix exports]
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Jiri Kosina <jikos@jikos.cz>
Cc: Dmitry Torokhov <dtor@mail.ru>
Acked-by: Alan Cox <alan@redhat.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index 71cf203..e458b08 100644
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -4004,6 +4004,7 @@
 		c |= 0x100;
 	return c;
 }
+EXPORT_SYMBOL_GPL(screen_glyph);
 
 /* used by vcs - note the word offset */
 unsigned short *screen_pos(struct vc_data *vc, int w_offset, int viewed)