Fix crash if LockErrorCleanup() is called twice

Fix crash if LockErrorCleanup() is called twice

The refactoring in commit 3c0fd64fec removed the clearing of
awaitedLock from LockErrorCleanup(). It's still needed, otherwise
LockErrorCleanup() during abort processing will try to update the
LOCALLOCK struct even after the lock has already been released. Put it
back.

Reported-by: Richard Guo 
Reported-by: Robins Tharakan 
Reported-by: Alexander Lakhin 
Discussion: https://www.postgresql.org/message-id/flat/CAMbWs4_dNX1SzBmvFdoY-LxJh_4W_BjtVd5i008ihfU-wFF=eg@mail.gmail.com
Discussion: https://www.postgresql.org/message-id/18832-38e5575b1bbd7277@postgresql.org
Discussion: https://www.postgresql.org/message-id/e11a30e5-c0d8-491d-8546-3a1b50c10ad4@gmail.com