meta-security-smack: rename layer in BBFILE variables
meta-security-smack: rename layer in BBFILE variables

The layer is not called meta-tizen-security. Its name is "security-smack",
with a pathname of "meta-security-smack". META_TIZEN_SECURITY can be removed
completely because it is not needed (in meta-tizen, such a variable was
used to find a default manifest, something that we no longer use here).

Signed-off-by: Patrick Ohly <0fc9d825c622b2a5ac5160289c29f03654b10648@intel.com>

pohly/meta-intel-iot-security,izaman/meta-intel-iot-security,acornea/meta-intel-iot-security,izaman/meta-intel-iot-security,pohly/meta-intel-iot-security,acornea/meta-intel-iot-security,acornea/meta-intel-iot-security,pohly/meta-intel-iot-security,01org/meta-intel-iot-security,01org/meta-intel-iot-security,izaman/meta-intel-iot-security,01org/meta-intel-iot-security,acornea/meta-intel-iot-security,01org/meta-intel-iot-security,izaman/meta-intel-iot-security,izaman/meta-intel-iot-security,acornea/meta-intel-iot-security