drm/vmwgfx: Add debugfs entries for various ttm resource managers

Use the newly added TTM's ability to automatically create debugfs entries
for specified placements. This creates debugfs files that can be read to
get information about various TTM resource managers which are used by
vmwgfx.

Signed-off-by: Zack Rusin <zackr@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220412033526.369115-3-zack@kde.org


Reviewed-by: Christian König <christian.koenig@amd.com>