Squashed 'features/nanostack/coap-service/' changes from f40072f..36d36ce

36d36ce Fixed compiler warnings (#98)

git-subtree-dir: features/nanostack/coap-service
git-subtree-split: 36d36ce17679f43a751d72d01820e774ff5e051c

source/coap_security_handler.c

@@ -196,6 +196,7 @@ void coap_security_destroy(coap_security_t *sec){
     }
 }
 
+#ifdef MBEDTLS_SSL_SRV_C
 /**** Random number functions ****/
 
 /**
@@ -265,6 +266,7 @@ static int simple_cookie_check(void *ctx,
     }
     return 0;
 }
+#endif // MBEDTLS_SSL_SRV_C
 
 /**** Key export function ****/
 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)