net: altera_tse: remove the useless parenthesis

Remove the useless parenthesis.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Chin Liang See <clsee@altera.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>