staging: dgnc: removes unused if defined code

DGNC_TRACER and TRC_TO_KMEM are never defined.

This patch removes if defined DGNC_TRACER and TRC_TO_KMEM code.

CC: Lidza Louina <lidza.louina@gmail.com>
CC: Mark Hounschell <markh@compro.net>
Signed-off-by: Seunghun Lee <waydi1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>