[lldb] Refactor Module::LookupInfo constructor

Module::LookupInfo's constructor currently goes over supported languages
trying to figure out the best way to search for a symbol name. This
seems like a great candidate for refactoring. Specifically, this is work
that can be delegated to language plugins.

Once again, the goal here is to further decouple plugins from
non-plugins. The idea is to have each language plugin take a name and
give you back some information about the name from the perspective of
the language. Specifically, each language now implements a
`GetFunctionNameInfo` method which returns an object of type
`Language::FunctionNameInfo`. Right now, it consists of a basename,
a context, and a FunctionNameType. Module::LookupInfo's constructor will
call `GetFunctionNameInfo` with the appropriate language plugin(s) and
then decide what to do with that information. I have attempted to maintain
existing behavior as best as possible.

A nice side effect of this change is that lldbCore no longer links
against the ObjC Language plugin.

Differential Revision: https://reviews.llvm.org/D108229