drm/ttm: add ttm_bo_move_to_lru_tail function v2

drm/ttm: add ttm_bo_move_to_lru_tail function v2

BugLink: http://bugs.launchpad.net/bugs/1546572
This allows the drivers to move a BO to the end of the LRU
without removing and adding it again.

v2: Make it more robust, handle pinned and swapable BOs as well.

Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit ab74961810ba7935b5f9643da10daaa36690f48e)
Signed-off-by: Alberto Milone <alberto.milone@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>