[PtrAuth] Use default attributes for some ptrauth intrinsics

This uses the default intrinsic attributes (nofree, nosync,
nocallback, willreturn) for a subset of the ptrauth intrinsics.
Notably, this does not use them for auth and resign, because these
intrinsics are specified to trap and as such are not willreturn.
As far as I understood, the remaining intrinsics may not trap
(or can only trap in cases where behavior is undefined).

Differential Revision: https://reviews.llvm.org/D137557