[clang] [clang] [MinGW] Explicitly always pass the -fno-use-init-array (PR #68571)

[Martin Storsjö via cfe-commits]

mstorsjo wrote:

> Right, so adding an `enum DefaultableBool { Default, False, True }` and changing the field to that value? 

With such a definition, I wonder how to interpret it for MSVC targets; `UseInitArray` would be false, as MSVC uses the `.CRT` sections, neither `.ctors` not `.init_array`. But it shouldn’t be reversed, and false currently means reversing it.

https://github.com/llvm/llvm-project/pull/68571