Calloc was already here, but not the others. Also add
manual type information.

These were in TargetLibraryInfo, but missing from RuntimeLibcalls.
This only adds the cases that already have the non-chk variants
already. Copies the enabled-by-default logic from TargetLibraryInfo,
which is probably overly permissive. Only isPS opts-out.

These are floating-point functions recorded in TargetLibraryInfo,
but missing from RuntimeLibcalls.

This is mostly the output of a vibe coded script running on
VecFuncs.def, with a lot of manual cleanups and fixing where the
vibes were off. This is not yet wired up to anything (except for the
handful of calls which are already manually enabled). In the future
the SystemLibrary mechanism needs to be generalized to allow plugging
these sets in based on the flag.

One annoying piece is there are some name conflicts across the libraries.
Some of the libmvec functions have name collisions with some sleef functions.
I solved this by just adding a prefix to the libmvec functions. It would
probably be a good idea to add a prefix to every group. It gets ugly,
particularly since some of the sleef functions started to use a Sleef_ prefix,
but mostly do not.

This kind of helper is higher level and not general enough to go directly
in SelectionDAG. Most similar utilities are in TargetLowering.

Makes linalg.reduce and linalg.map region_ops so they can be constructed
from functions and be called as decorators.

Resolves #148131

- Unlock `std::optional<T&>` implementation
- Allow instantiations of `optional<T(&)(...)>` and `optional<T(&)[]>`
but disables `value_or()` and `optional::iterator` + all `iterator`
related functions
- Update documentation
- Update tests

Only use RuntimeLibcallsInfo. Remove the helper functions used to
transition.