Mac - DNS Search Domains Not Being Used When redirect_dns is true

[dmalloy54]

The configured search domains are never added to the array being used to actually configure them (as instantiated here):
https://github.com/OpenVPN/openvpn3/blob/master/openvpn/tun/mac/macdns.hpp#L173

I successfully tested out a fix by replacing the above line with newly created helper function:

CF::MutableArray search_domains(CF::mutable_array_from_array(config.search_domains));

And adding the helper to cf.hpp:

inline MutableArray mutable_array_from_array(Array array, const CFIndex capacity= 0)  
{ 
    return MutableArray(CFArrayCreateMutableCopy(kCFAllocatorDefault, capacity, array()));  
}