[Ravenwood] Load native code without class load hook

Since we rely on Android's native log infrastructure for Ravenwood's own
logging, we always need to load libandroid_runtime.so. To reduce
Ravenwood environment bootstrapping complexity, we load the native code
as soon as possible.

Test: $ANDROID_BUILD_TOP/frameworks/base/ravenwood/scripts/run-ravenwood-tests.sh
Flag: EXEMPT host test change only
Bug: 356918135
Change-Id: I4ee50e0b6b48a69d60de71a770e9ab3add4cdb17