module
Possibly fix https://github.com/llvm/llvm-project/issues/96693
The direct reason is that we are calculating the linkage for the
declaration too early so that the linkage got calculated incorrectly.
And after I look into the problem, I found it is completely not
necessary to calculate the linkage there. It is for ModulesTS. So I
simply removes that legacy experimental code and fix the issue.
