Dalvik: DMB Optimisation

Replaces use of 'dmb' and 'dmb st' with inner-shareable versions.
This should improve performance in certain cases without harming
correctness.

Change-Id: Id30f58b93b34bf0e232bb01dc3956a82f7a69c40
Dalvik: DMB Optimisations for TracingJIT

Makes DMB domain ISH or ISHST instead of the implicit System.
ISH (Inner Shareable) should be sufficient for all cores/clusters,
but is not sufficient for GPU or other memory-mapped peripherals

Change-Id: Id159228daba97bc3692d2eb1ee2786bae2ee34a7