i915/gtt: fix ordering issues with status setup and DMAR

This code was setting up the status page before setting the DMAR-is-on-bit,
so we were getting DMAR errors on the status page. Reverse the two bits
of init code to the correct result.
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/char/agp/intel-gtt.c

@@ -688,14 +688,14 @@ static int intel_gtt_init(void)
 
 	intel_private.base.stolen_size = intel_gtt_stolen_size();
 
+	intel_private.base.needs_dmar = USE_PCI_DMA_API && INTEL_GTT_GEN > 2;
+
 	ret = intel_gtt_setup_scratch_page();
 	if (ret != 0) {
 		intel_gtt_cleanup();
 		return ret;
 	}
 
-	intel_private.base.needs_dmar = USE_PCI_DMA_API && INTEL_GTT_GEN > 2;
-
 	return 0;
 }