Introduce hwasan mode for linker

This mode instructs the linker to search for libraries in hwasan
subdirectories of all library search paths. This is set up to contain a
hwasan-enabled copy of libc, which is needed for HWASan programs to
operate. There are two ways this mode can be enabled:

* for native binaries, by using the linker_hwasan64 symlink as its
  interpreter
* for apps: by setting the LD_HWASAN environment variable in wrap.sh

Bug: 276930343
Change-Id: I0f4117a50091616f26947fbe37a28ee573b97ad0
diff --git a/linker/linker_config.h b/linker/linker_config.h
index fe23ec1..09fea45 100644
--- a/linker/linker_config.h
+++ b/linker/linker_config.h
@@ -166,6 +166,7 @@
   static bool read_binary_config(const char* ld_config_file_path,
                                  const char* binary_realpath,
                                  bool is_asan,
+                                 bool is_hwasan,
                                  const Config** config,
                                  std::string* error_msg);