Staging: altera: move .h file to proper place

Staging drivers should be self-contained, without files in the include/
directories.  So move the altera.h file back to the driver directory for
now, until it moves out of the staging tree.

Cc: Igor M. Liplianin <liplianin@netup.ru>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>