Rationalize logging.

Rationalize logging.

Replacing stray uses of LOGI them with macros specific to functional
aspects of the collector.  Replace (void *) cast for with (void) cast
in the expansion of unused macros.  While these are both no-ops, the
latter cast does not emit a warning message.  Lastly, eliminate some
logging statements I never found useful.  More logging statements need
to be culled.

Change-Id: Id5603c3a816c016a91e00e296ff5c16dddfe7e1a