Clean up the argument list for MarshalInfo::MarshalInfo

[jkoritzinsky]

The constructor for MarshalInfo in mlinfo.h and mlinfo.cpp has a ton of arguments, many of which are booleans. We should clean up this argument list and create a structure/flags that describe the various settings to make calls to the constructor readable.

[AaronRobinsonMSFT]

Given we are looking at source generators going forward, I don't think this is worth doing.