fixed output-configuration for PCA10028
fixed output-configuration for PCA10028

PCA10028 has no LED_0 and uses LED_2 instead

ihassin/nRF51-ble-bcast-mesh,ihassin/nRF51-ble-bcast-mesh,mrquincle/nRF51-ble-bcast-mesh,mrquincle/nRF51-ble-bcast-mesh,mrquincle/nRF51-ble-bcast-mesh,mrquincle/nRF51-ble-bcast-mesh