Add c typedefs for the Sony PSP

[overdrivenpotato]

This adds support for PSP targets to build important libraries like libpanic_unwind.

[rust-highfive]

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[overdrivenpotato]

The CI failure seems to be spurious, given that this PR does not touch android:

+ ./sdk/tools/bin/avdmanager create+ grep -v =
 avd --name arm --package system-images;android-24;google_apis;armeabi-v7a
Error: Package path is not valid. Valid system image paths are:
null

[JohnTitor]

The failure should be fixed by #1754, could you rebase?

[overdrivenpotato]

Sure, just rebased

[JohnTitor]

Thanks! I'm going to merge but it'd be great if we could add CI for this target like the Nintendo Switch, when you add more items or have time anyway.

[overdrivenpotato]

Sure, I’ll give it a shot soon. Going to try and get a basic PSP target into rustc first.

[tesuji]

I wonder those constants is needed as you can use c_int::MAX.