Change the first input parameter in mlxreg_hotplug_device_create to the
pointer to mlxreg_hotplug private data in order to use the fields from
the private data structure.
Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
[dvhart: Cleaned up commit message]
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>