drm/i915/gem: Remove reference to struct drm_device.pdev

drm/i915/gem: Remove reference to struct drm_device.pdev

References to struct drm_device.pdev should not be used any longer as
the field will be moved into the struct's legacy section. Add a fix
for the rsp commit.

v2:
	* fix an error in the commit description (Michael)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Fixes: d57d4a1daf5e ("drm/i915: Create stolen memory region from local memory")
Cc: CQ Tang <cq.tang@intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Xinyun Liu <xinyun.liu@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: "Thomas Hellström" <thomas.hellstrom@intel.com>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: intel-gfx@lists.freedesktop.org
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210427174857.7862-1-tzimmermann@suse.de