drm/i915 + agp/intel-gtt: prep work for direct setup

To be able to directly set up the intel-gtt code from drm/i915 and
avoid setting up the fake-agp driver we need to prepare a few things:
- pass both the bridge and gpu pci_dev to the probe function and add
  code to handle the gpu pdev both being present (for drm/i915) and
  not present (fake agp).
- add refcounting to the remove function so that unloading drm/i915
  doesn't kill the fake agp driver

v2: Fix up the cleanup and refcount, noticed by Jani Nikula.

Reviewed-by: Jani Nikula <jani.nikula@linux.intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/char/agp/intel-agp.c

@@ -12,6 +12,7 @@
 #include <asm/smp.h>
 #include "agp.h"
 #include "intel-agp.h"
+#include <drm/intel-gtt.h>
 
 int intel_agp_enabled;
 EXPORT_SYMBOL(intel_agp_enabled);
@@ -747,7 +748,7 @@ static int __devinit agp_intel_probe(struct pci_dev *pdev,
 
 	bridge->capndx = cap_ptr;
 
-	if (intel_gmch_probe(pdev, bridge))
+	if (intel_gmch_probe(pdev, NULL, bridge))
 		goto found_gmch;
 
 	for (i = 0; intel_agp_chipsets[i].name != NULL; i++) {
@@ -824,7 +825,7 @@ static void __devexit agp_intel_remove(struct pci_dev *pdev)
 
 	agp_remove_bridge(bridge);
 
-	intel_gmch_remove(pdev);
+	intel_gmch_remove();
 
 	agp_put_bridge(bridge);
 }