drmmode: don't store drmModeEncoder
drmmode: don't store drmModeEncoder

The DRM encoder is only used to populate the xf86Output possible_clones
and possible_crtc fields.  There is no reason to store it.

Signed-off-by: Daniel Kurtz <31914e832df1cd8e5daa417106c0c6f5297b27d7@chromium.org>

BUG=chromium:370411
TEST=sanity check ui

Change-Id: I9a29f89ba1d38d66b224994723233801b716b03a
Reviewed-on: https://chromium-review.googlesource.com/198369
Reviewed-by: Sean Paul <f9352ecf3e2294bdb914c99cca8d12601acec118@chromium.org>
Commit-Queue: Daniel Kurtz <31914e832df1cd8e5daa417106c0c6f5297b27d7@chromium.org>
Tested-by: Daniel Kurtz <31914e832df1cd8e5daa417106c0c6f5297b27d7@chromium.org>

markyzq/armsoc-rockchip,markyzq/armsoc-rockchip