[GWP-ASan] Export GWP-ASan regions to libdebuggerd.

Exports GWP-ASan allocator information callbacks to libdebuggerd so that
tombstoned can get information from the GWP-ASan allocator in the case
of a crash.

Bug: 135634846
Test: atest bionic-unit-tests

Change-Id: Ie16426af55602fb2a76c4e69217773354c365843
diff --git a/linker/linker_debuggerd_android.cpp b/linker/linker_debuggerd_android.cpp
index b8c82f9..42ea2b7 100644
--- a/linker/linker_debuggerd_android.cpp
+++ b/linker/linker_debuggerd_android.cpp
@@ -39,6 +39,12 @@
       return __libc_shared_globals()->abort_msg;
     },
     .post_dump = &notify_gdb_of_libraries,
+    .get_gwp_asan_state = []() {
+      return __libc_shared_globals()->gwp_asan_state;
+    },
+    .get_gwp_asan_metadata = []() {
+      return __libc_shared_globals()->gwp_asan_metadata;
+    },
   };
   debuggerd_init(&callbacks);
 }