bpo-32898: Fix debug build crash with COUNT_ALLOCS

[eduardo-elizondo]

The following build crashed:
mkdir debug && cd debug
../configure --with-pydebug
make EXTRA_CFLAGS="-DCOUNT_ALLOCS"

The bug was introduced in: 25420fe

Fix:

1. s/inter/interp/
2. Declare PyTypeObject

https://bugs.python.org/issue32898

[the-knights-who-say-ni]

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[eduardo-elizondo]

Signed CLA. It should be ready within a couple of hours?

[serhiy-storchaka]

Yes, it should be ready within a couple of hours.

Please add your name in Misc/ACKS and add a news entry (you can use the blurb utility as described in the developer guide).

[eduardo-elizondo]

Ready!

[miss-islington]

Thanks @eduardo-elizondo for the PR, and @benjaminp for merging it 🌮🎉.. I'm working now to backport this PR to: 3.7.
🐍🍒⛏🤖

[bedevere-bot]

GH-5806 is a backport of this pull request to the 3.7 branch.