Export __lsan_init

[jakubjelinek]

Summary

lsan_preinit.cc is meant to be linked into executable and calls lsan_init from .preinit_array section.
But if liblsan is a shared library, then this doesn't work, because the symbol is not exported.
This patch fixes that.
The counterparts like asan_init or __tsan_init already do have SANITIZER_INTERFACE_ATTRIBUTE.

[jakubjelinek]

Can you please commit it?

compiler-rt/trunk/lib/lsan/lsan.h

void GetStackTrace(__sanitizer::BufferedStackTrace *stack,
   }
 }
 
 }  // namespace __lsan
 
 extern bool lsan_inited;
 extern bool lsan_init_is_running;
 
-extern "C" void __lsan_init();
+extern "C" SANITIZER_INTERFACE_ATTRIBUTE void __lsan_init();