MINOR: threads: Use __decl_hathreads instead of #ifdef/#endif

A #ifdef/#endif on USE_THREAD was added in the commit 0048dd04 ("MINOR: threads:
Fix build when we're not compiling with threads.") to conditionally define the
start_lock variable, because HA_SPINLOCK_T is only defined when HAProxy is
compiled with threads.

If fact, to do that, we should use the macro __decl_hathreads instead.

If commit 0048dd04 is backported in 1.8, this one can also be backported.
1 file changed