drm/xe/display: reduce includes in compat i915_drv.h

Remove some unnecessary includes, and replace xe_device.h with the
sufficient xe_device_types.h.
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ada73d5e3565b1cc284405386a16cc74d79bbb05.1717004739.git.jani.nikula@intel.com

drivers/gpu/drm/xe/compat-i915-headers/i915_drv.h

@@ -12,11 +12,9 @@
 
 #include <drm/drm_drv.h>
 
-#include "soc/intel_pch.h"
-#include "xe_device.h"
-#include "i915_reg_defs.h"
 #include "i915_utils.h"
 #include "intel_runtime_pm.h"
+#include "xe_device_types.h"
 
 static inline struct drm_i915_private *to_i915(const struct drm_device *dev)
 {