Restrict HAL network access to HALS that manage network hardware

Only HALs that manage networks need network capabilities and network
sockets.

Test: aosp_marlin and aosp_bullhead policy builds. Note: neverallow
      rules are compile time assertions and do not change the
      on-device policy.
Bug: 36185625

Change-Id: Id64846eac24cf72ed91ce775cecb2c75f11b78df