netdev: fix network interface flag
netdev: fix network interface flag

The setting of the RUNNING flag is missing. This patch modifies the
conditional statement so that it can be set even if IFF_DOWN.

Change-Id: I74cdd335805ba74f52dc7571059199e9a27d9bf2
Signed-off-by: Junhwan Park <7fee488b6f78fc50b291ffc7d10428788977e877@samsung.com>

JunhwanPark/TizenRT,JunhwanPark/TizenRT,JunhwanPark/TizenRT,JunhwanPark/TizenRT,JunhwanPark/TizenRT,JunhwanPark/TizenRT