Start using Providers instead of direct module access

Export information about static libraries, shared libraries and
exported flags through Providers instead of accessing the module
directly.  Much more is left to be converted, but this significantly
simplifies the dependencies on libraries with stubs by making it easy
for a module to masquerade as another by simply exporting the
providers from the other module.  Instead of depending on all the
versions of a library and then picking which one to use later, it
can depend only on the implementation variant and then select the
right SharedLibraryInfo from the variant.

Test: m checkbuild
Test: only expected changes to build.ninja
Change-Id: I1fd9eb4d251cf96ed8398d586efc3e0817663c76