BUG/MINOR: stick-table: fix build with DEBUG_THREAD

Compilation is broken with DEBUG_THREAD since the following patch
  76642223f014f89cd1f374291798499f4fba7dde
  MEDIUM: stick-table: switch the table lock to rwlock

Fix this by updating a legacy HA_SPIN_INIT() to HA_RWLOCK_INIT().

No backport needed unless the mentionned patch is backported.
1 file changed