Fix crash on linux mint 22 with nodelist

Fixes #1661

The issue was that with gcc13, a missing return statement doesn't get
generated as a return from the function.  Older GCC versions seem to
add in this missing RET.

There may be more of these with gcc-13, will need to look for warnings
if they exist (I didn't see one for this).

sdk/fido/nodelist.cpp

@@ -172,6 +172,7 @@ bool Nodelist::AddEntry(uint16_t zone, uint16_t net, NodelistEntry& e) {
   FidoAddress address(zone, net, e.number(), 0, domain_);
   e.address(address);
   entries_.emplace(address, e);
+  return true;
 }
 
 bool Nodelist::HandleLine(const std::string& line, uint16_t& zone, uint16_t& region, uint16_t& net, uint16_t& hub) {