message: Fix repeated warning with two calls to to_package_id_specs
diff: @@ -369,16 +369,15 @@ pub fn create_bcx<'a, 'cfg>(
  let target_data = RustcTargetData::new(ws, &build_config.requested_kinds)?;
  let all_packages = &Packages::All;
  - let full_specs = if rustdoc_scrape_examples.is_some() {
  + let need_reverse_dependencies = rustdoc_scrape_examples.is_some();
  + let full_specs = if need_reverse_dependencies {
  all_packages
  } else {
  spec
  };
  - let specs = spec.to_package_id_specs(ws)?;
  let resolve_specs = full_specs.to_package_id_specs(ws)?;
  - let has_dev_units =
  - if filter.need_dev_deps(build_config.mode) || rustdoc_scrape_examples.is_some() {
  + let has_dev_units = if filter.need_dev_deps(build_config.mode) || need_reverse_dependencies {
  HasDevUnits::Yes
  } else {
  HasDevUnits::No
  @@ -422,6 +421,11 @@ pub fn create_bcx<'a, 'cfg>(
  // Find the packages in the resolver that the user wants to build (those
  // passed in with `-p` or the defaults from the workspace), and convert
  // Vec<PackageIdSpec> to a Vec<PackageId>.
  + let specs = if need_reverse_dependencies {
  + spec.to_package_id_specs(ws)?
  + } else {
  + resolve_specs.clone()
  + };
  let to_build_ids = resolve.specs_to_ids(&specs)?;
  // Now get the `Package` for each `PackageId`. This may trigger a download
  // if the user specified `-p` for a dependency that is not downloaded.
  