BUILD: threads: Rename SPIN/RWLOCK macros using HA_ prefix

This remove any name conflicts, especially on Solaris.
diff --git a/include/common/buffer.h b/include/common/buffer.h
index c6fb2fe..acaa79a 100644
--- a/include/common/buffer.h
+++ b/include/common/buffer.h
@@ -751,13 +751,13 @@
 
 static inline void offer_buffers(void *from, unsigned int threshold)
 {
-	SPIN_LOCK(BUF_WQ_LOCK, &buffer_wq_lock);
+	HA_SPIN_LOCK(BUF_WQ_LOCK, &buffer_wq_lock);
 	if (LIST_ISEMPTY(&buffer_wq)) {
-		SPIN_UNLOCK(BUF_WQ_LOCK, &buffer_wq_lock);
+		HA_SPIN_UNLOCK(BUF_WQ_LOCK, &buffer_wq_lock);
 		return;
 	}
 	__offer_buffer(from, threshold);
-	SPIN_UNLOCK(BUF_WQ_LOCK, &buffer_wq_lock);
+	HA_SPIN_UNLOCK(BUF_WQ_LOCK, &buffer_wq_lock);
 }
 
 /*************************************************************************/