Dependencies on vkparse.hinc were spreading through the code which I
didn't want as that removes a lot of the automation from the automake
files. This keeps all parser code internal to vkparse.c's scope, and any
accesses required for enum and struct (not yet) definitions can be
fetched by name.
It worked as a proof of concept, but as the code itself needs to be a
bit smarter, it would be a lot smarter to break up that code to make it
easier to work on the individual parts.