msm8974-common: Set TARGET_NEEDS_NETD_DIRECT_CONNECT_RULE to true

* Due to "specialness" in our RIL library, ConnectivityService
  doesn't seem to appropriately add the relevant directly-
  connected routes, meaning that IPv4 mobile data is inoperable
  due to lack of a default route. Let's reenable the legacy netd
  behavior to get our connectivity back.

Change-Id: I59f8476ab36db0fb79856f74346e62e0dd4abae0