Put IPSec's anouncement of its successful intialisation under bootverbose:

now that it's a default kernel option, we don't really need to tell the
world about it on every boot, especially as it won't be used by most users.

sys/netipsec/key.c

@@ -7640,7 +7640,8 @@ key_init(void)
 	/* initialize key statistics */
 	keystat.getspi_count = 1;
 
-	printf("IPsec: Initialized Security Association Processing.\n");
+	if (bootverbose)
+		printf("IPsec: Initialized Security Association Processing.\n");
 }
 
 #ifdef VIMAGE