The pattern of a power well backing a set of fuses whose initialization
we need to wait for during power well enabling is common to all GEN9+
platforms. Adding support for this to the HSW power well enable helper
allows us to use the HSW/BDW power well code for GEN9+ as well in a
follow-up patch.

v2:
- Use an enum for power gates instead of raw numbers. (Ville)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NArkadiusz Hiler <arkadiusz.hiler@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170711204236.5618-6-imre.deak@intel.comSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>