misc: mic: Use PTR_ERR_OR_ZERO rather than its implementation

PTR_ERR_OR_ZERO contains if(IS_ERR(...)) + PTR_ERR. It is better to
use it directly. hence just replace it.
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Link: https://lore.kernel.org/r/1567665795-5901-3-git-send-email-zhongjiang@huawei.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mic/scif/scif_epd.h

@@ -156,9 +156,8 @@ static inline int scif_verify_epd(struct scif_endpt *ep)
 static inline int scif_anon_inode_getfile(scif_epd_t epd)
 {
 	epd->anon = anon_inode_getfile("scif", &scif_anon_fops, NULL, 0);
-	if (IS_ERR(epd->anon))
-		return PTR_ERR(epd->anon);
-	return 0;
+
+	return PTR_ERR_OR_ZERO(epd->anon);
 }
 
 static inline void scif_anon_inode_fput(scif_epd_t epd)