[AGPGART] Make sure we don't give up searching for gfx cards.

We need to clear the previously found cap_ptr, or we exit after
finding the first one, even if its not the one plugged into the
bridge we're looking at.
Signed-off-by: Dave Jones <davej@redhat.com>

drivers/char/agp/generic.c

@@ -639,6 +639,7 @@ u32 agp_collect_device_status(struct agp_bridge_data *bridge, u32 requested_mode
 		if ((device->bus->self->vendor != bridge->dev->vendor) &&
 			(device->bus->self->device != bridge->dev->device)) {
 			pci_dev_put(device);
+			cap_ptr = 0;
 			continue;
 		}
 	}