libdasd: Free memory for previously used sysfs path

util_path_sysfs() allocates memory for the created path which must be
freed by the user.

Fixes: 8023a72b11 ("libdasd: Provide function to read ese sysfs attribute")
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>

libdasd/dasd_sys.c

@@ -91,6 +91,7 @@ int dasd_sys_ese(char *devnode)
 
 	rc = fgetc(fp) - '0';
 	fclose(fp);
+	free(path);
 
 	return (rc == 1) ? 1 : 0;
 }