[llvm] [MC] Explicitly request executable stacks (PR #93478)

[Roger Ferrer Ibáñez via llvm-commits]

rofirrim wrote:

Thanks @MaskRay .

@vzakhari @kiranchandramohan would it make sense to allocate the trampoline buffer somewhere else other than the stack? Say in the heap and free it upon leaving the function (it needs to be allocated just once per function as it is conceptually a temporary of the argument evaluation, so in that sense it is a bit like an `allocatable`).

https://github.com/llvm/llvm-project/pull/93478