hwmon: use module_pci_driver

This patch converts the drivers in drivers/hwmon/* to use module_pci_driver()
macro which makes the code smaller and a bit simpler.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: Rudolf Marek <r.marek@assembler.cz>
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>