staging:dgnc:Fixes use of deprecated headers in dgnc_cls.c

Fixes use of deprecated header <asm/io.h> in staging:dgnc:dgnc_cls.c

Signed-off-by: Archana kumari <archanakumari959@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>