Code Generation of complex parameter types

[TobiasWienand]

I think it would also be good to add support to our code generation machinery to generate functions with more complex parameters. The place for that would be here:

fuzzilli/Sources/Fuzzilli/Base/ProgramBuilder.swift

Line 425 in 7b2850d

public func randomParameters(n wantedNumberOfParameters: Int? = nil) -> SubroutineDescriptor {

Maybe this makes most sense as a follow-up change though, so we can land this one first to get the compiler support and then see if it's easy to also get codegen support.

Originally posted by @saelo in #449 (comment)