[OpaquePtr] Remove checking pointee type for byval/preallocated type

These currently always require a type parameter. The bitcode reader
already upgrades old bitcode without the type parameter to use the
pointee type.

In cases where the caller does not have byval but the callee does, we
need to follow CallBase::paramHasAttr() and also look at the callee for
the byval type so that CallBase::isByValArgument() and
CallBase::getParamByValType() are in sync. Do the same for preallocated.

While we're here add a corresponding version for inalloca since we'll
need it soon.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D104663