[CIR] React to breaking change to DataLayoutTypeInterface (#128772)

In #128754, `DataLayoutTypeInterface` was changed to give
`getPreferredAlignment` a default implemention. As a result, table-gen
no longer declared `getPreferredAlignment` when defining a class that
contained `[DeclareTypeInterfaceMethods<DataLayoutTypeInterface>]` in
the table-gen definition. That means all of the definitions in
`CIRTypes.cpp`, such as `PointerType::getPreferredAligment`, were
compilation errors.

Delete all the definitions of `getPreferredAlignment`. I verified that
the default implementation does the exact same thing as the explicit
overrides that are being deleted.

0 files changed, 0 insertions, 0 deletions