[clang] [flang] [flang][driver] Remove Fortain_main static library from linking stages (PR #75816)

[Michael Klemm via cfe-commits]

mjklemm wrote:

@banach-space How did you draw the pictures in the MD file that I'm changing?  If you have some sort of source file, I can try to add a nice chart to the explanation, I'm adding.

https://github.com/llvm/llvm-project/pull/75816