[PATCH -next] mtd: docg3: Fix passing zero to 'PTR_ERR' warning in doc_probe_device

[YueHaibing]

Fix a static code checker warning:
drivers/mtd/devices/docg3.c:1875
 doc_probe_device() warn: passing zero to 'ERR_PTR'

Fixes: ae9d4934b2d7 ("mtd: docg3: add multiple floor support")
Signed-off-by: YueHaibing <yuehaib...@huawei.com>
---
 drivers/mtd/devices/docg3.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c
index 4c94fc0..60ddc38 100644
--- a/drivers/mtd/devices/docg3.c
+++ b/drivers/mtd/devices/docg3.c
@@ -1872,7 +1872,7 @@ doc_probe_device(struct docg3_cascade *cascade, int 
floor, struct device *dev)
 nomem2:
        kfree(docg3);
 nomem1:
-       return ERR_PTR(ret);
+       return ret ? ERR_PTR(ret) : NULL;
 }
 
 /**
-- 
2.7.0