Disable parse_headers feature

Bazel has a parse_headers feature which expects headers to be
independently buildable. While a nice way to partially enforce IWYU,
it's broken. See https://github.com/bazelbuild/bazel/issues/23460.

Until the Bazel issue is fixed, we'll need to turn that off. In
particular, after https://github.com/bazelbuild/bazel/pull/22369,
parse_headers is no longer silently inactive.

This does not remove the need to do something about the fips_fragment
filenames. Those come from the layering_check feature, rather than the
parse_headers feature. We also have a number of headers that don't
actually work standalone and, by the style guide, probably should be
named .inc:
https://google.github.io/styleguide/cppguide.html#Self_contained_Headers

But since the feature does not work anyway, just turn it off for now.

Bug: 362664827
Change-Id: I9646d722a59f92be81848cf5a586738cc5f3dac4
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/70687
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: Bob Beck <bbe@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
diff --git a/BUILD.bazel b/BUILD.bazel
index d3b66ee..9e7b430 100644
--- a/BUILD.bazel
+++ b/BUILD.bazel
@@ -44,6 +44,12 @@
 )
 load(":util/util.bzl", "bssl_cc_binary", "bssl_cc_library", "bssl_cc_test")
 
+# Disable the parse_headers feature. It does not work well in C right now. See
+# https://github.com/bazelbuild/bazel/issues/23460 for details. When that is
+# fixed, if enabled, we likely also need to rename some headers to .inc per
+# https://google.github.io/styleguide/cppguide.html#Self_contained_Headers
+package(features = ["-parse_headers"])
+
 licenses(["notice"])
 
 exports_files(["LICENSE"])