Make bazel option --collect_symbol_counts a noop

Our reasoning:
* it only works with gold
* it was broken for the last 3 months (since unknown commit) (silently did
nothing and nobody complained)
* we see almost zero usage of this option

RELNOTES: None.
PiperOrigin-RevId: 228116158
diff --git a/third_party/com/github/bazelbuild/bazel/src/main/protobuf/crosstool_config.proto b/third_party/com/github/bazelbuild/bazel/src/main/protobuf/crosstool_config.proto
index b79e5d2..361710d 100644
--- a/third_party/com/github/bazelbuild/bazel/src/main/protobuf/crosstool_config.proto
+++ b/third_party/com/github/bazelbuild/bazel/src/main/protobuf/crosstool_config.proto
@@ -352,6 +352,7 @@
 
   // Feature flags.
   // TODO(bazel-team): Sink those into 'Feature' instances.
+  // Legacy field, ignored by Bazel.
   optional bool supports_gold_linker = 10 [default = false];
   // Legacy field, ignored by Bazel.
   optional bool supports_thin_archives = 11 [default = false];