drm/msm/dpu: move hw_inf encoder baseclass

Both video and command physical encoders will have
a hw interface assigned to it. So there is really no
need to track the hw block in specific encoder subclass.

Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1550107156-17625-2-git-send-email-jsanka@codeaurora.org


Signed-off-by: Rob Clark <robdclark@chromium.org>