*: migrate to CC toolchains and Bazel 5.4.0

Change-Id: Iff3c0ddda4413dd0c5fa657a5b7813223e98611e
Reviewed-on: https://review.monogon.dev/c/monogon/+/1079
Tested-by: Jenkins CI
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
diff --git a/build/toolchain/cc_toolchain_config.bzl b/build/toolchain/cc_toolchain_config.bzl
index cebf18f..7a949fa 100644
--- a/build/toolchain/cc_toolchain_config.bzl
+++ b/build/toolchain/cc_toolchain_config.bzl
@@ -167,6 +167,10 @@
             name = "strip",
             path = "/bin/false",
         ),
+        tool_path(
+            name = "objcopy",
+            path = "/usr/bin/objcopy",
+        ),
     ]
 
     return cc_common.create_cc_toolchain_config_info(