Fix FTBFS

../../build/modules/linux-x64/module.modulemap:11:12: error: header '../../linux/debian_bullseye_amd64-sysroot/usr/include/alloca.h' not found
   11 |     header "../../linux/debian_bullseye_amd64-sysroot/usr/include/alloca.h"
      |            ^
1 error generated

diff -up chromium-141.0.7390.37/build/config/BUILDCONFIG.gn.me chromium-141.0.7390.37/build/config/BUILDCONFIG.gn
--- chromium-141.0.7390.37/build/config/BUILDCONFIG.gn.me	2025-10-01 17:39:47.242174153 +0200
+++ chromium-141.0.7390.37/build/config/BUILDCONFIG.gn	2025-10-01 17:49:54.736578295 +0200
@@ -557,6 +557,8 @@ foreach(_target_type,
         ]) {
   template(_target_type) {
     target(_target_type, target_name) {
+      use_libcxx_modules = false
+
       forward_variables_from(invoker, "*", TESTONLY_AND_VISIBILITY)
       forward_variables_from(invoker, TESTONLY_AND_VISIBILITY)
       if (!defined(inputs)) {
@@ -660,6 +662,8 @@ foreach(_target_type,
       # TODO(crbug.com/326584510): Reclient doesn't respect this variable, see
       # rbe_bug_326584510_missing_inputs in //build/config/clang/clang.gni
       _uses_cflags = false
+      use_libcxx_modules = false
+ 
       if (defined(sources)) {
         foreach(f, sources) {
           if (string_replace(f + ".END", ".cc.END", "") != f + ".END" ||