Check iotivity-lite stack init before processing requests

[jkralik]

check if the iotivity-lite stack is initialized before processing new requests during shutdown.

#0  0x00007f5052dfa213 in ...
#1  0x00007f505306325f in ...
#2  0x00007f50527d1935 in oc_core_device_handler () from target:/lib/libiotivity-lite-client-server.so.2
#3  0x00007f50527e0fb1 in oc_ri_invoke_coap_entity_handler () from target:/lib/libiotivity-lite-client-server.so.2
#4  0x00007f50527eb799 in coap_receive () from target:/lib/libiotivity-lite-client-server.so.2
#5  0x00007f50527ec5b1 in process_thread_g_coap_engine () from target:/lib/libiotivity-lite-client-server.so.2
#6  0x00007f50527c8bb4 in call_process () from target:/lib/libiotivity-lite-client-server.so.2
#7  0x00007f50527c8f16 in do_event () from target:/lib/libiotivity-lite-client-server.so.2
#8  0x00007f50527c8f36 in oc_process_run () from target:/lib/libiotivity-lite-client-server.so.2
#9  0x00007f50527d8c96 in oc_main_poll () from target:/lib/libiotivity-lite-client-server.so.2
#10 0x00007f50527e26dc in oc_ri_shutdown () from target:/lib/libiotivity-lite-client-server.so.2
#11 0x00007f50527d8cc7 in oc_main_shutdown () from target:/lib/libiotivity-lite-client-server.so.2

[ocf-conformance-test-tool]

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[sonarcloud]

SonarCloud Quality Gate failed.   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

78.9% Coverage
0.0% Duplication

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