hwc: remove waiting for fence in copybit and avoid sending to mdp

- Waiting for acquired fence is not required in copybit draw as Frame
  Buffer target is used for copybit output after egl swap
- Avoid sending the acquiredFence fd to the MDP for those layers which
  are marked for copybit.

Change-Id: I433c16a2c26b03691e6e259fd8cfcb1b37ef8786