kdbus: Add a null teminated string for GetConnectionCredentials (LinuxSecurityLabel) method.
The result of LinuxSecurityLabel item should end to null.
Dbus spec : https://dbus.freedesktop.org/doc/dbus-specification.html
Legacy dbus daemon : dbus/bus/driver.c. _dbus_asv_add_byte_array (&array_iter, "LinuxSecurityLabel", s, strlen (s) + 1))
libdbus kdbus : dbus-transport-kdbus.c. dbus_bool_t res = _dbus_asv_add_byte_array (&array_iter, "LinuxSecurityLabel", info.sec_label, strlen (info.sec_label)+1);
Signed-off-by: INSUN PYO <insun.pyo@samsung.com>
Change-Id: Idff013ca4c56d93a6207bcb7365b36da86f7c1c2