Add OCaml compiler support

[topolarity]

No description provided.

[topolarity]

Tried to run the tests locally but ran into:

Caused by:
  failed to create directory `/usr/share/testsuite/rust/cargo_build/target`

Caused by:
  Cross-device link (os error 18)
# ...
    [2] autobuild(dir::AbstractString, src_name::AbstractString, src_version::VersionNumber, sources::Vector{<:AbstractSource}, script::AbstractString, platforms::Vector, products::Vector{<:Product}, dependencies::Vector{<:AbstractDependency}; verbose::Bool, debug::Bool, skip_audit::Bool, ignore_audit_errors::Bool, autofix::Bool, code_dir::Union{Nothing, String}, require_license::Bool, dont_dlopen::Bool, kwargs::Base.Pairs{Symbol, V, Tuple{Vararg{Symbol, N}}, NamedTuple{names, T}} where {V, N, names, T<:Tuple{Vararg{Any, N}}})
      @ BinaryBuilder ~/repos/BinaryBuilder.jl/src/AutoBuild.jl:932
    [3] (::var"#25#27"{Platform, Vector{Platform}})(build_path::String)
      @ Main ~/repos/BinaryBuilder.jl/test/building.jl:132

[giordano]

JuliaPackaging/BinaryBuilderBase.jl#395