[clang] [llvm] [Android] Drop workarounds for older Android API levels (PR #161893)

[Dan Albert via llvm-commits]

DanAlbert wrote:

I'll be dropping support for 22 and older in r31.  We should have the final toolchain for r30 already. We haven't yet created the OS branch which will provide the sysroot for r31, and likely won't until early next year. That doesn't matter for either of the two workarounds being removed here though, so the current form of the PR is fine by me to merge whenever. @pirama-arumuga-nainar should confirm from the toolchain side though.

https://github.com/llvm/llvm-project/pull/161893