argument of inline_mysql_mutex_init in sql_base.cc.

When initializing LOCK_dd_owns_lock_open mutex pass
correct PSI key instead of NULL value.

mysql-test/suite/perfschema/r/dml_setup_instruments.result:
  Updated test results after adding P_S instrumentation
  for LOCK_dd_owns_lock_open.
sql/sql_base.cc:
  When initializing LOCK_dd_owns_lock_open mutex pass
  correct PSI key instead of NULL value.