drm/etnaviv: take etnaviv_gem_obj in etnaviv_gem_mmap_obj

This function will be changed to be called indirectly and this
prototype change brings it in line with all the other indirect
object calls.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>

drivers/gpu/drm/etnaviv/etnaviv_gem.c

@@ -129,10 +129,9 @@ void etnaviv_gem_put_pages(struct etnaviv_gem_object *etnaviv_obj)
 	/* when we start tracking the pin count, then do something here */
 }
 
-static int etnaviv_gem_mmap_obj(struct drm_gem_object *obj,
+static int etnaviv_gem_mmap_obj(struct etnaviv_gem_object *etnaviv_obj,
 		struct vm_area_struct *vma)
 {
-	struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
 	pgprot_t vm_page_prot;
 
 	vma->vm_flags &= ~VM_PFNMAP;
@@ -151,9 +150,9 @@ static int etnaviv_gem_mmap_obj(struct drm_gem_object *obj,
 		 * in particular in the case of mmap'd dmabufs)
 		 */
 		fput(vma->vm_file);
-		get_file(obj->filp);
+		get_file(etnaviv_obj->base.filp);
 		vma->vm_pgoff = 0;
-		vma->vm_file  = obj->filp;
+		vma->vm_file  = etnaviv_obj->base.filp;
 
 		vma->vm_page_prot = vm_page_prot;
 	}
@@ -173,7 +172,7 @@ int etnaviv_gem_mmap(struct file *filp, struct vm_area_struct *vma)
 	}
 
 	obj = to_etnaviv_bo(vma->vm_private_data);
-	return etnaviv_gem_mmap_obj(vma->vm_private_data, vma);
+	return etnaviv_gem_mmap_obj(obj, vma);
 }
 
 int etnaviv_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)