samples: crypto: Fix EC-JPake sample error handling

Fix EC-JPake sample not checking the error code on helper function.
The sample will then compare two unitialized arrays and report error
on if they are equal or not, instead of failing the sample when
key derivation has failed.

Signed-off-by: Joakim Andersson <[email protected]>

Author: joerchan

samples/crypto/ecjpake/src/main.c

@@ -216,8 +216,15 @@ int main(void)
 	uint8_t server_secret[32];
 	uint8_t client_secret[32];
 
-	do_key_derivation(&server, server_secret, sizeof(server_secret));
-	do_key_derivation(&client, client_secret, sizeof(client_secret));
+	status = do_key_derivation(&server, server_secret, sizeof(server_secret));
+	if (status != PSA_SUCCESS) {
+		goto error;
+	}
+
+	status = do_key_derivation(&client, client_secret, sizeof(client_secret));
+	if (status != PSA_SUCCESS) {
+		goto error;
+	}
 
 	PRINT_HEX("server_secret", server_secret, sizeof(server_secret));
 	PRINT_HEX("client_secret", client_secret, sizeof(client_secret));