Staging: hv: remove DPRINT_EXIT macro

No need for it, use the built-in kernel function tracing instead
if you really need something like this.

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