TS-1938: remove unnecessary thread_id() wrapper in reclaimable freelist

pthread_self() on x86 can accesses a register on CPU, it's quite
fast enough.

So thread_id() wrapper is unnecessary, let's drop it.

Signed-off-by: Yunkai Zhang <qiushu.zyk@taobao.com>
Enable assertions for the clang static analyzer

The clang analyzer needs to see all assertions so that it knows to
trim the call graph. This greatly reduces the number of false NULL
dereferences.