[clang] [llvm] [clang][driver] Set TLSDESC as the default for Android on RISC-V (PR #81198)

[Fangrui Song via llvm-commits]

https://github.com/MaskRay approved this pull request.

LGTM once the `!isAndroidVersionLT(29)` check is removed.

https://github.com/llvm/llvm-project/pull/81198