[llvm] RuntimeLibcalls: Fix reporting incorrectly typed fp128 long double functions (PR #214944)

[Sharjeel Khan via llvm-commits]

Sharjeel-Khan wrote:

Hey @arsenm, we started seeing `ld.lld: error: no libcall available for fmaxnum` in Android for x86-64. I could be mistaken but I think you might have forgotten to add the libcalls back based on `isLongDoubleF128` for x86-64 target like in `X86CommonLibcalls`. 

https://github.com/llvm/llvm-project/pull/214944