Frees custom allocated ODB data. This should only be called when
memory allocated using git_odb_backend_data_alloc is not returned
to libgit2 because the backend encountered an error in the read
function after allocation and did not return this data to libgit2.
Frees custom allocated ODB data. This should only be called when memory allocated using git_odb_backend_data_alloc is not returned to libgit2 because the backend encountered an error in the read function after allocation and did not return this data to libgit2.