Init `out struct` parameters to prevent NullReferenceException

[UlyssesWu]

Reason:

https://github.com/Tencent/InjectFix/blob/552da3654e74c4b08bbe2533699fb2306df5de7e/Source/VSProj/Src/Core/StackOperation.cs#L256-L260

Known issue, but never fixed😅

Test case:

        public struct TestStruct
        {
            public int a;
            public string b;
        }

        [Patch]
        public void TestOutStruct(out TestStruct ts)
        {
            ts.a = 114514;
            ts.b = "buggy IFix";
        }

        public void Awake() // must not be [Patch]ed
        {
            TestStruct ts;
            TestOutStruct(out ts);
        }

[tencent-adm]

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