tipc: use min() to simplify the code

When calculating size of own domain based on number of peers, the result
should be less than MAX_MON_DOMAIN, so using min() here is very semantic.

Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20240822133908.1042240-8-lizetao1@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/tipc/monitor.c

@@ -149,7 +149,7 @@ static int dom_size(int peers)
 
 	while ((i * i) < peers)
 		i++;
-	return i < MAX_MON_DOMAIN ? i : MAX_MON_DOMAIN;
+	return min(i, MAX_MON_DOMAIN);
 }
 
 static void map_set(u64 *up_map, int i, unsigned int v)