CLEANUP: wdt: do not remap SI_TKILL to SI_LWP, test the values directly

We used to remap SI_TKILL to SI_LWP when SI_TKILL was not available
(e.g. FreeBSD) but that's ugly and since we need this only in a single
switch/case block in wdt.c it's even simpler and cleaner to perform the
two tests there, so let's do this.

include/haproxy/compat.h

@@ -23,7 +23,6 @@
 #define _HAPROXY_COMPAT_H
 
 #include <limits.h>
-#include <signal.h>
 #include <unistd.h>
 /* This is needed on Linux for Netfilter includes */
 #include <sys/param.h>
@@ -154,11 +153,6 @@ typedef struct { } empty_t;
 #define F_SETPIPE_SZ (1024 + 7)
 #endif
 
-/* On FreeBSD we don't have SI_TKILL but SI_LWP instead */
-#if !defined(SI_TKILL) && defined(SI_LWP)
-#define SI_TKILL SI_LWP
-#endif
-
 #if defined(USE_TPROXY) && defined(USE_NETFILTER)
 #include <linux/types.h>
 #include <linux/netfilter_ipv6.h>

src/wdt.c

@@ -104,11 +104,21 @@ void wdt_handler(int sig, siginfo_t *si, void *arg)
 
 		/* No doubt now, there's no hop to recover, die loudly! */
 		break;
-#ifdef USE_THREAD
+
+#if defined(USE_THREAD) && defined(SI_TKILL) /* Linux uses this */
+
 	case SI_TKILL:
 		/* we got a pthread_kill, stop on it */
 		thr = tid;
 		break;
+
+#elif defined(USE_THREAD) && defined(SI_LWP) /* FreeBSD uses this */
+
+	case SI_LWP:
+		/* we got a pthread_kill, stop on it */
+		thr = tid;
+		break;
+
 #endif
 	default:
 		/* unhandled other conditions */