[asan] Disable dlopen interceptor on Android.

It can not work, as libdl is always first in the lookup order,
even ahead of LD_PRELOAD-ed libraries.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@209657 91177308-0d34-0410-b5e6-96231b3b80d8