Staging: hv: fix up some coding style issues in logging.h

It's now clean.

Well, from a coding style guide, not from a logic standpoint, the whole
file needs to be tossed overboard and cheered on as the sharks tear it
to individual bits.

Cc: Hank Janssen <hjanssen@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>