Merge binary input for benchmark vectors

This allows rhs vectors in Ginkgo's binary format to be used in solver benchmarks.
This is necessary to do bitwise reproductions of solver executions, since the MatrixMarket format writer
rounds its numbers by default.

Related PR: #1584

benchmark/solver/solver_common.hpp

@@ -288,7 +288,7 @@ struct SolverGenerator : DefaultSystemGenerator<> {
     {
         if (config.contains("rhs")) {
             std::ifstream rhs_fd{config["rhs"].get<std::string>()};
-            return gko::read<Vec>(rhs_fd, std::move(exec));
+            return gko::read_generic<Vec>(rhs_fd, std::move(exec));
         } else {
             gko::dim<2> vec_size{system_matrix->get_size()[0], FLAGS_nrhs};
             if (FLAGS_rhs_generation == "1") {