drm/nouveau/iccsense: switch to instanced constructor

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>

drm/nouveau/iccsense: implement for ina209, ina219 and ina3221

based on Martins initial work

v3: fix ina2x9 calculations
v4: don't kmalloc(0), fix the lsb/pga stuff
v5: add a field to tell if the power reading may be invalid
add nkvm_iccsense_read_all function
check for the device on the i2c bus

Signed-off-by: Karol Herbst <nouveau@karolherbst.de>
Reviewed-by: Martin Peres <martin.peres@free.fr>