bpo-35780: Fix errors in lru_cache() C code (GH-11623)

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+Fix lru_cache() errors arising in recursive, reentrant, or
+multi-threaded code. These errors could result in orphan links and in
+the cache being trapped in a state with fewer than the specified maximum
+number of links.  Fix handling of negative maxsize which should have
+been treated as zero.  Fix errors in toggling the "full" status flag.
+Fix misordering of links when errors are encountered.  Sync-up the C
+code and pure Python code for the space saving path in functions with a
+single positional argument. In this common case, the space overhead of
+an lru cache entry is reduced by almost half.  Fix counting of cache
+misses. In error cases, the miss count was out of sync with the actual
+number of times the underlying user function was called.