cleanup: add a load statement (#3698)

Author: krasimirgg

rust/private/dummy_cc_toolchain/dummy_cc_toolchain.bzl

@@ -1,6 +1,7 @@
 """Cc toolchain definitions for use on wasm platforms"""
 
 load("@rules_cc//cc/common:cc_common.bzl", "cc_common")
+load("@rules_cc//cc/toolchains:cc_toolchain_config_info.bzl", "CcToolchainConfigInfo")
 
 def _dummy_cc_toolchain_impl(_ctx):
     # The `all_files` attribute is referenced by rustc_compile_action().