CHROMIUM: drm/rockchip: Fix the call to drm_gem_put_pages()

CHROMIUM: drm/rockchip: Fix the call to drm_gem_put_pages()

When freeing the buffer we don't have any means of determining if the
buffer was read or written, so we must assume both and pass true for
both arguments of drm_gem_put_pages(). Let's fix the code which
currently passes false.

BUG=chrome-os-partner:56378
TEST=while true; do backlight_dbus_tool --set --percent=0 && sleep 8 &&
 backlight_dbus_tool --set --percent=100 && sleep 3 ; done

Change-Id: I7da2fd81e7e728e0ef242837b70819c4a3aee7bf
Signed-off-by: Tomasz Figa <tfiga@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/382934
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Randy Li <randy.li@rock-chips.com>