Broken links for file that has a filename that begins with an underscore

[soegaard]

There seems to be a problem with links to files that has a filename that begins with an underscore.

Example:

On this page:

https://llvm-mos.github.io/llvm-mos-sdk/c64_8h.html

The top three links:
https://llvm-mos.github.io/llvm-mos-sdk/__vic2_8h_source.html
https://llvm-mos.github.io/llvm-mos-sdk/__sid_8h_source.html
https://llvm-mos.github.io/llvm-mos-sdk/__6526_8h_source.html
all result in an 404 error.