drm/i915/glk: Implement core display init/uninit sequence for geminilake

The sequence is pretty much the same as broxton, except that bspec
requires the AUX domains to be enabled. But since those can't be enabled
before the phys are initialized, we just use the same sequence as
broxton.

v2: Don't manually enable AUX domains. (Ander)

Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1480667037-11215-9-git-send-email-ander.conselvan.de.oliveira@intel.com