shiboken6: Clean up member variables of the generators

There used to be a lot hash/list member variables in the generators,
some of them static.

Refactor this to:
- Use initializer lists.
- Introduce static functions returning a const ref
  to const hashes and lists and put them
  closer to where they are needed.
- Move m_tpfuncs to cppgenerator.
- Introduce a special struct for protocol function
  entries for clarity.

As a drive by. streamline and fix
CppGenerator::writeTypeAsMappingDefinition(),
CppGenerator::writeTypeAsNumberDefinition() to generate nullptr and
reinterpret_cast and not populate hashes with empty strings.

Change-Id: Id1d067dec7769568f56b77ccafca843e01f99b0b
Reviewed-by: Christian Tismer <tismer@stackless.com>

0 files changed, 0 insertions, 0 deletions