[llvm] RuntimeLibcalls: Really move default libcall handling to tablegen (PR #148780)

[Matt Arsenault via llvm-commits]

arsenm wrote:

> > AVR also has the strange reuse of the f64 names for the f32 sin and cos
> 
> I haven’t looked but would guess this platform and MSP have pretty much the same issue as f128 on 32-bit/x86, since `float` and `double` are the same size. 

I'm not really sure what the issue is. The implementation is very underdeveloped if it's that broad. The starting state only bothered to handle sin and cos 

https://github.com/llvm/llvm-project/pull/148780