[tlbuild] Solaris 11.4 build error

[Andreas Scherer]

Hello, Rainer,

 > However, I don't know how to patch the sources so that the build
 > process runs without manual intervention.
 > Does anyone have a suggestion?
I've hacked the TWILL changefile for TL'2023 and renamed 'ref_link' to 
'ref_lnk'. Thanks for spotting this. (Alternatively, we could add the 
POSIX-option for Solaris 11.4 and this single WEB code, but I can't test 
this approach.)

Greetings,
Andreas