use std/libdevice erf in inductor (#89388)
By itself, libdevice version of erf has the same perf as our decomposition, but in real workloads it leads to better fusion groups (due to fewer ops in the fused kernel).
Bonus: a few fp64 test skips removed, because our decomposition wasn't accurate enough for fp64, but libdevice version is.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/89388
Approved by: https://github.com/jansel
