netfilter: xtables: remove bogus mangle table dependency of connmark

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>

net/netfilter/Kconfig

@@ -318,7 +318,6 @@ config NETFILTER_XT_TARGET_CLASSIFY
 
 config NETFILTER_XT_TARGET_CONNMARK
 	tristate  '"CONNMARK" target support'
-	depends on IP_NF_MANGLE || IP6_NF_MANGLE
 	depends on NF_CONNTRACK
 	depends on NETFILTER_ADVANCED
 	select NF_CONNTRACK_MARK