drm/i915: use pdev_to_i915() instead of pci_get_drvdata() directly

We have a helper for converting pci device to i915 device, use it.

v2: Also convert i915_pci_probe() (Gustavo)

Reviewed-by: Gustavo Sousa <gustavo.sousa@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240812103415.1540096-1-jani.nikula@intel.com


Signed-off-by: Jani Nikula <jani.nikula@intel.com>