SkMallocPixelRef::MakeDirect: doesn't need a release proc

Change-Id: Ic84b52b128b7cd71f0870094c5787d588ed68a9d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/234326
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>

src/core/SkMallocPixelRef.cpp

@@ -50,7 +50,7 @@ sk_sp<SkPixelRef> SkMallocPixelRef::MakeDirect(const SkImageInfo& info,
     if (!is_valid(info)) {
         return nullptr;
     }
-    return sk_sp<SkPixelRef>(new SkMallocPixelRef(info, addr, rowBytes, nullptr, nullptr));
+    return sk_make_sp<SkPixelRef>(info.width(), info.height(), addr, rowBytes);
 }