oniro-sysctl: Fix typo in net option

Fix typo in net.ipv4.config.default.log_martians (now conf)

Signed-off-by: Davide Gardenal <davide.gardenal@huawei.com>

meta-oniro-core/recipes-core/oniro-sysctl/oniro-sysctl/oniro-net-ipv4.conf

@@ -16,4 +16,4 @@ net.ipv4.conf.all.send_redirects = 0
 net.ipv4.conf.default.accept_source_route = 0
 
 # Log packets with impossible addresses to kernel log
-net.ipv4.config.default.log_martians = 1
+net.ipv4.conf.default.log_martians = 1