Staging: hv: remove timer wrapper functions

Use a real timer (there's only one in the code), no wrapper is needed,
it just increases the complexity for no reason.

Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Hank Janssen <hjanssen@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>