drm/ttm: add ttm_sys_manager v3

Add a separate manager for the system domain and make function tables
mandatory.

v2: debug is still optional
v3: return void during init

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210430092508.60710-1-christian.koenig@amd.com

drm/ttm: drop sysfs directory

Not used any more.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210208133226.36955-3-christian.koenig@amd.com

drm/ttm: add debugfs directory v2

As far as I can tell the buffer_count was never used by an
userspace application.

The number of BOs in the system is far better suited in
debugfs than sysfs and we now should be able to add other
information here as well.

v2: add that additionally to sysfs

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/414954/

drm/ttm/drivers: remove unecessary ttm_module.h include v2

ttm_module.h deals with internals of TTM and should never
be include outside of it.

v2: also move the file around

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/404885/