vm: reduce logcat debug spam

this ought to prevent:
D/dalvikvm(12407): Trying to load lib libjavacore.so 0x0
D/dalvikvm(12407): Added shared lib libjavacore.so 0x0
D/dalvikvm(12407): No JNI_OnLoad found in libnativehelper.so 0x0, skipping init
D/dalvikvm(12407): Note: class Landroid/app/ActivityManagerNative; has 180 unimplemented (abstract) methods

Change-Id: I3e6017404e2ec4c85a502071db0d12fb40ff5a56