network/aria2: Minor build fix wrt bash4.
network/aria2: Minor build fix wrt bash4.

panosmdma/SlackOnly-SlackBuilds,panosmdma/SlackOnly-SlackBuilds,panosmdma/SlackOnly-SlackBuilds,panosmdma/SlackOnly-SlackBuilds,panosmdma/SlackOnly-SlackBuilds,panosmdma/SlackOnly-SlackBuilds,panosmdma/SlackOnly-SlackBuilds