remove consolemap.h from header exports

Remove linux/consolemap.h from make headers_install

It contains no user interfaces.
The defines in this file are used only for kernel internal state.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>