v4.64

This release is using the same codebase as left by Philippe Jounin, no changes were made other than to the build system to support Github Actions.

Checksums
tftpd64-x86-v4.64.zip: 68bb4a0fa26870e6d94d91d7e3b63b041b6aa00ed13532b93ff1cb4dbe86c589
tftpd64-x64-v4.64.zip: de420761400500a8f942057966d85c3dec4d4f3eb72e148046b5c69b344e0274