Fix coverity defects: CID 147606, 147609

coverity scan CID:147606, Type:resource leak
coverity scan CID:147609, Type:resource leak

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: cao.xuewen <cao.xuewen@zte.com.cn>
Closes #5245

tests/zfs-tests/cmd/dir_rd_update/dir_rd_update.c

@@ -108,6 +108,7 @@ main(int argc, char **argv)
 			}
 			j++;
 		}
+		(void) close(fd);
 	} else if (pid == 0) {
 		int fd = open(dirpath, O_RDONLY);
 		int chownret;
@@ -128,6 +129,7 @@ main(int argc, char **argv)
 
 			k++;
 		}
+		(void) close(fd);
 	}
 
 	return (0);