drm/i915: Use ARRAY_SIZE() instead of hand rolling it

A couple of hand rolled ARRAY_SIZE()s caught my eye. Get rid of them.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c
index c98098e..25d74d2 100644
--- a/drivers/gpu/drm/i915/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/intel_sdvo.c
@@ -63,7 +63,7 @@
 	"SECAM_60"
 };
 
-#define TV_FORMAT_NUM  (sizeof(tv_format_names) / sizeof(*tv_format_names))
+#define TV_FORMAT_NUM  ARRAY_SIZE(tv_format_names)
 
 struct intel_sdvo {
 	struct intel_encoder base;