[package] firewall:

[package] firewall:
	- defer firewall start until the first interface is brought up by hotplug, fixes race conditions on slow devices
	- create a file lock during firewall start and wait for it in hotplug events, prevents race conditions between start and addif
	- start firewall actions in background from hotplug handler since the firewall itself fires further hotplug events which results in a deadlock if not forked off
	- get loaded state direcly from the uci binary since updated value is not recognized by config_get after uci_set_state
	- bump package revision to r2

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@21486 3c298f89-4303-0410-b956-a3cf2f4a3e73