Remove async_safe references.

The only reason async_safe was being used was to avoid allocations.
However, on bionic, using dprintf also avoids allocations, so use that
function instead.

Test: Ran memory_replay before and after on a trace and verified all
Test: output is the same.
Test: Added malloc_disable/malloc_enable around all dprintf calls to
Test: verify they do not allocate.
Change-Id: I4f1f304bcbabfde529bba281f0a735345dfd312a
4 files changed