verify_file: Add constness to a few addresses.

We should not touch any data while verifying packages (or parsing the
in-memory ASN.1 structures).

Test: mmma bootable/recovery
Test: recovery_component_test passes.
Test: recovery_unit_test passes.
Change-Id: Ie990662c6451ec066a1807b3081c9296afbdb0bf

install.cpp

@@ -589,7 +589,7 @@ bool verify_package(const unsigned char* package_data, size_t package_size) {
   // Verify package.
   ui->Print("Verifying update package...\n");
   auto t0 = std::chrono::system_clock::now();
-  int err = verify_file(const_cast<unsigned char*>(package_data), package_size, loadedKeys,
+  int err = verify_file(package_data, package_size, loadedKeys,
                         std::bind(&RecoveryUI::SetProgress, ui, std::placeholders::_1));
   std::chrono::duration<double> duration = std::chrono::system_clock::now() - t0;
   ui->Print("Update package verification took %.1f s (result %d).\n", duration.count(), err);