staging: dgnc: Remove extra curly braces

Remove unnecessary curly braces of if statements in dgnc_neo.c and
dgnc_tty.c to meet kernel coding style.

Signed-off-by: Masaru Nomura <massa.nomura@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>