Soong support for Scudo

Scudo is a hardened usermode allocator that is part of LLVM's compiler-rt
project (home of the Sanitizers). clang allows for -fsanitize=scudo as a
possible command line option to link the shared Scudo library to a binary.

This patch add Scudo as a potential sanitize option. Scudo is not compatible
with ASan and TSan and will be disabled if either is enabled.

Bug: 72112048
Test: aosp compiled with m -j
Test: local experiment with scudo: true to ensure that a test target
(tombstoned) could be linked with scudo.

Change-Id: I76bb6c60891d4782f6665a112c4c2bf7c31645da