Make android_mallopt weak for native bridge

It is not intercepted by malloc hooks.

Test: bionic-unit-tests --gtest_filter=android_mallopt*
Change-Id: I3fb4101bdcdb62d82a09212fda9eafff7f43c786
diff --git a/libc/bionic/malloc_common_dynamic.cpp b/libc/bionic/malloc_common_dynamic.cpp
index 0ac3f62..eec49a4 100644
--- a/libc/bionic/malloc_common_dynamic.cpp
+++ b/libc/bionic/malloc_common_dynamic.cpp
@@ -465,6 +465,7 @@
 // =============================================================================
 // Platform-internal mallopt variant.
 // =============================================================================
+__BIONIC_WEAK_FOR_NATIVE_BRIDGE
 extern "C" bool android_mallopt(int opcode, void* arg, size_t arg_size) {
   if (opcode == M_SET_ZYGOTE_CHILD) {
     if (arg != nullptr || arg_size != 0) {