tilegx: request_irq with a non-null device name

This patch simply makes the tilegx net driver call request_irq with a
non-null name. It makes the output in /proc/interrupts more obvious, but
also helps tools that don't expect to find null there.

Signed-off-by: Simon Marchi <simon.marchi@polymtl.ca>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: David S. Miller <davem@davemloft.net>