PCI: hv: Remove unused reason for refcount handler

The get/put functions were taking a reason code. This appears to be
a debug infrastructure that is no longer used.

Move the functions to start of file to eliminate need for
forward declaration. Forward declarations are discouraged on
Linux.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
[lorenzo.pieralisi@arm.com: updated commit subject]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>