drm/nouveau/core: remove nouveau_mm.mutex, no more users

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/core/core/mm.c

@@ -208,7 +208,6 @@ nouveau_mm_init(struct nouveau_mm *mm, u32 offset, u32 length, u32 block)
 	struct nouveau_mm_node *node;
 
 	if (block) {
-		mutex_init(&mm->mutex);
 		INIT_LIST_HEAD(&mm->nodes);
 		INIT_LIST_HEAD(&mm->free);
 		mm->block_size = block;

drivers/gpu/drm/nouveau/core/include/core/mm.h

@@ -15,8 +15,6 @@ struct nouveau_mm {
 	struct list_head nodes;
 	struct list_head free;
 
-	struct mutex mutex;
-
 	u32 block_size;
 	int heap_nodes;
 };

drivers/gpu/drm/nouveau/nouveau_ttm.c

@@ -111,7 +111,7 @@ nouveau_vram_manager_debug(struct ttm_mem_type_manager *man, const char *prefix)
 	struct nouveau_mm_node *r;
 	u32 total = 0, free = 0;
 
-	mutex_lock(&mm->mutex);
+	mutex_lock(&nv_subdev(pfb)->mutex);
 	list_for_each_entry(r, &mm->nodes, nl_entry) {
 		printk(KERN_DEBUG "%s %d: 0x%010llx 0x%010llx\n",
 		       prefix, r->type, ((u64)r->offset << 12),
@@ -121,7 +121,7 @@ nouveau_vram_manager_debug(struct ttm_mem_type_manager *man, const char *prefix)
 		if (!r->type)
 			free += r->length;
 	}
-	mutex_unlock(&mm->mutex);
+	mutex_unlock(&nv_subdev(pfb)->mutex);
 
 	printk(KERN_DEBUG "%s  total: 0x%010llx free: 0x%010llx\n",
 	       prefix, (u64)total << 12, (u64)free << 12);