[hwasan] Suppress leaks from dlsym with hwasan+lsan just like with asan+lsan

[leonardchan]

Summary

We should follow suite with how asan handles this now that lsan also works with hwasan.

[vitalybuka]

@kstoimenov Does this fix any leaks you see?

compiler-rt/lib/hwasan/hwasan_allocation_functions.cpp

 #include "sanitizer_common/sanitizer_tls_get_addr.h"
 
 #if !SANITIZER_FUCHSIA
 
 using namespace __hwasan;
 
 struct DlsymAlloc : public DlSymAllocator<DlsymAlloc> {
   static bool UseImpl() { return !hwasan_inited; }
+  static void OnAllocate(const void *ptr, uptr size) {
+#  if CAN_SANITIZE_LEAKS
+    // Suppress leaks from dlerror(). Previously dlsym hack on global array was
+    // used by leak sanitizer as a root region.
+    __lsan_register_root_region(ptr, size);
+#  endif
+  }
+  static void OnFree(const void *ptr, uptr size) {
+#  if CAN_SANITIZE_LEAKS
+    __lsan_unregister_root_region(ptr, size);
+#  endif
+  }
 };
 
 extern "C" {
 
 SANITIZER_INTERFACE_ATTRIBUTE
 int __sanitizer_posix_memalign(void **memptr, uptr alignment, uptr size) {
   GET_MALLOC_STACK_TRACE;
   CHECK_NE(memptr, 0);