[PATCH] Minor Python simplifications

[Joel Brobecker]

Hi Tom,

> I noticed that a few "#if"s could be removed from the Python code.
> This patch is the result.
> 
> gdb/ChangeLog
> 2020-10-29  Tom Tromey  <tromey@adacore.com>
> 
> 	* python/python.c: Consolidate two HAVE_PYTHON blocks.
> 	(python_GdbModuleDef): Move earlier.  Now static.
> 	(do_start_initialization): Consolidate some IS_PY3K blocks.

Thanks for the patch. It looks good to me!

-- 
Joel