core: wait for dependencies before continuing with device activation

Before jumping to activation stage 1, make sure dependencies are activated.

include/NetworkManager.h

@@ -486,6 +486,9 @@ typedef enum {
 	/* Infiniband device does not support connected mode */
 	NM_DEVICE_STATE_REASON_INFINIBAND_MODE = 49,
 
+	/* A dependency of the connection failed */
+	NM_DEVICE_STATE_REASON_DEPENDENCY_FAILED = 50,
+
 	/* Unused */
 	NM_DEVICE_STATE_REASON_LAST = 0xFFFF
 } NMDeviceStateReason;