Update filesystem permissions in atrace.rc to give selinux control.

These were previously restricted to shell user, but now that some apps
that require access, such as Traceur, are no longer running as the shell
user, these permissions must be loosened.

Selinux will now control access rights to these files completely, rather
than using a combination of unix permissions and selinux permissions.

- Removed chown sections because they're not necessary with chmod 666
- Included both debug and non-debug directory structures in
atrace_userdebug.rc

Bug: 68126425
Test: Traceur (outside of shell user) and command-line atrace both function.
Change-Id: Ie1ba4328a5cb3b9647acf9ef6e8aeeba61cb4961