drm/i915/gtt: Fix typo in fill_px() macro

The macro declared the ppgtt parameter but implicitly used the local vm
instead.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180606205128.25952-1-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_gem_gtt.c

@@ -528,8 +528,8 @@ static void cleanup_page_dma(struct i915_address_space *vm,
 
 #define setup_px(vm, px) setup_page_dma((vm), px_base(px))
 #define cleanup_px(vm, px) cleanup_page_dma((vm), px_base(px))
-#define fill_px(ppgtt, px, v) fill_page_dma((vm), px_base(px), (v))
-#define fill32_px(ppgtt, px, v) fill_page_dma_32((vm), px_base(px), (v))
+#define fill_px(vm, px, v) fill_page_dma((vm), px_base(px), (v))
+#define fill32_px(vm, px, v) fill_page_dma_32((vm), px_base(px), (v))
 
 static void fill_page_dma(struct i915_address_space *vm,
 			  struct i915_page_dma *p,