Before, that API was part of the analyzers themselves, which meant we
couldn't disable a packet analyzer before it had been instantiated.
That's different from protocol/file analyzers, where we disable them
through the corresponding component. The lack of the component-side
API prevented Spicy from replacing packet analyzers at startup.
The reason we had put this into analyzer originally was performance so
that we don't need a component lookup for every packet. This change
keeps that optimization by caching the on/off state in the analyzer
itself as well, but now with the component being the one controlling
it.
