drm/ast: Remove last traces of struct ast_gem_object

The ast driver has switched to struct drm_vram_gem_object a while ago.
This patch removes a function and forward declaration that were forgotten
before.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191107083404.6852-2-tzimmermann@suse.de

drivers/gpu/drm/ast/ast_drv.h

@@ -137,8 +137,6 @@ struct ast_private {
 int ast_driver_load(struct drm_device *dev, unsigned long flags);
 void ast_driver_unload(struct drm_device *dev);
 
-struct ast_gem_object;
-
 #define AST_IO_AR_PORT_WRITE		(0x40)
 #define AST_IO_MISC_PORT_WRITE		(0x42)
 #define AST_IO_VGA_ENABLE_PORT		(0x43)
@@ -289,10 +287,6 @@ extern void ast_mode_fini(struct drm_device *dev);
 int ast_mm_init(struct ast_private *ast);
 void ast_mm_fini(struct ast_private *ast);
 
-int ast_gem_create(struct drm_device *dev,
-		   u32 size, bool iskernel,
-		   struct drm_gem_object **obj);
-
 /* ast post */
 void ast_enable_vga(struct drm_device *dev);
 void ast_enable_mmio(struct drm_device *dev);

drivers/gpu/drm/ast/ast_main.c

@@ -535,27 +535,3 @@ void ast_driver_unload(struct drm_device *dev)
 	pci_iounmap(dev->pdev, ast->regs);
 	kfree(ast);
 }
-
-int ast_gem_create(struct drm_device *dev,
-		   u32 size, bool iskernel,
-		   struct drm_gem_object **obj)
-{
-	struct drm_gem_vram_object *gbo;
-	int ret;
-
-	*obj = NULL;
-
-	size = roundup(size, PAGE_SIZE);
-	if (size == 0)
-		return -EINVAL;
-
-	gbo = drm_gem_vram_create(dev, &dev->vram_mm->bdev, size, 0, false);
-	if (IS_ERR(gbo)) {
-		ret = PTR_ERR(gbo);
-		if (ret != -ERESTARTSYS)
-			DRM_ERROR("failed to allocate GEM object\n");
-		return ret;
-	}
-	*obj = &gbo->bo.base;
-	return 0;
-}