Not seeding this each call should help reduce collisions when multiple
threads are calling ashmem_create_region. Also cleaned up code by
deleting gotos, and making formatting consistent.
Bug: 15394258
Change-Id: Iafdaea57b2317e0eb7c40d7b5595c523814fd88c
This is needed by the MemoryFile changes in
https://android-git.corp.google.com/g/2714
where it is used to find out whether a file descriptor
refers to an ashmem region.
