[Nouveau] [PATCH] drm/nouveau/gem: fix err_cast.cocci warnings

[kernel test robot]

From: kernel test robot <lkp at intel.com>

drivers/gpu/drm/nouveau/nouveau_gem.c:589:9-16: WARNING: ERR_CAST can be used with mem


 Use ERR_CAST inlined function instead of ERR_PTR(PTR_ERR(...))

Generated by: scripts/coccinelle/api/err_cast.cocci

CC: Markus Elfring <elfring at users.sourceforge.net>
Signed-off-by: kernel test robot <lkp at intel.com>
---

url:    https://github.com/0day-ci/linux/commits/Markus-Elfring/drm-nouveau-gem-Use-vmemdup_user-rather-than-duplicating-its-implementation/20200812-150757
base:   git://anongit.freedesktop.org/drm-intel for-linux-next

 nouveau_gem.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/nouveau/nouveau_gem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_gem.c
@@ -586,7 +586,7 @@ u_memcpya(uint64_t user, unsigned nmemb,
 	size *= nmemb;
 	mem = vmemdup_user(userptr, size);
 	if (IS_ERR(mem))
-		return ERR_PTR(PTR_ERR(mem));
+		return ERR_CAST(mem);
 
 	return mem;
 }