drm/i915/bios: prefer using dev_priv over dev pointer

dev_priv is the new black. Or something.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450271061-32646-3-git-send-email-jani.nikula@intel.com
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index fe60b44..18be127 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -3355,7 +3355,7 @@
 extern void intel_i2c_reset(struct drm_device *dev);
 
 /* intel_bios.c */
-int intel_bios_init(struct drm_device *dev);
+int intel_bios_init(struct drm_i915_private *dev_priv);
 bool intel_bios_is_valid_vbt(const void *buf, size_t size);
 
 /* intel_opregion.c */