Disabled logging alerts to syslog.

It feels to be causing more harm than good, because syslog() can be blocking,
which is even more critical under resource exhaustion conditions when some
alerts are expected.

src/nxt_log.c

@@ -66,7 +66,10 @@ nxt_log_set_ctx(nxt_log_t *log, nxt_log_ctx_handler_t handler, void *ctx)
 void nxt_cdecl
 nxt_log_handler(nxt_uint_t level, nxt_log_t *log, const char *fmt, ...)
 {
-    u_char   *p, *syslogmsg, *end;
+    u_char   *p, *end;
+#if 0
+    u_char   *syslogmsg;
+#endif
     va_list  args;
     u_char   msg[NXT_MAX_ERROR_STR];
 
@@ -79,7 +82,9 @@ nxt_log_handler(nxt_uint_t level, nxt_log_t *log, const char *fmt, ...)
         *p++ = ' ';
     }
 
+#if 0
     syslogmsg = p;
+#endif
 
     p = nxt_sprintf(p, end, (log->ident != 0) ? "[%V] *%D " : "[%V] ",
                     &nxt_log_levels[level], log->ident);
@@ -100,6 +105,7 @@ nxt_log_handler(nxt_uint_t level, nxt_log_t *log, const char *fmt, ...)
 
     (void) nxt_write_console(nxt_stderr, msg, p - msg);
 
+#if 0
     if (level == NXT_LOG_ALERT) {
         *(p - nxt_length("\n")) = '\0';
 
@@ -109,4 +115,5 @@ nxt_log_handler(nxt_uint_t level, nxt_log_t *log, const char *fmt, ...)
          */
         nxt_write_syslog(LOG_ALERT, syslogmsg);
     }
+#endif
 }