Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/43859
This frees up the `reactnative` CMake target so we could use it as single .so
for the CMake build.
Changelog:
[Internal] [Changed] - Rename reactnative.a -> react_cxxreact.a
Reviewed By: javache
Differential Revision: D55745640
fbshipit-source-id: 3cad512cc07a277af2a0cea696863c85a17dabc1