Fix buffer overflow

tests/test.c

@@ -226,7 +226,7 @@ int main() {
 
     ok(rnode_set_made_time(&rn, 3200) == 0, "Set manufacture time & date"); 
 
-    uint8_t checksum[11] = {0};
+    uint8_t checksum[16] = {0};
 
     ok(rnode_calculate_checksum(&rn, checksum) == 0, "Calculate checksum");