drm/vmwgfx: Remove vmwgfx_hashtab

drm/vmwgfx: Remove vmwgfx_hashtab

[ Upstream commit 9da30cdd6a318595199319708c143ae318f804ef ]

The vmwgfx driver has migrated from using the hashtable in vmwgfx_hashtab
to the linux/hashtable implementation. Remove the vmwgfx_hashtab from the
driver.

Signed-off-by: Maaz Mombasawala <mombasawalam@vmware.com>
Reviewed-by: Martin Krastev <krastevm@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
Signed-off-by: Zack Rusin <zackr@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-12-zack@kde.org
Stable-dep-of: a309c7194e8a ("drm/vmwgfx: Remove rcu locks from user resources")
Signed-off-by: Sasha Levin <sashal@kernel.org>