UB fix

[newling]

Since #1033 I have not been able to compile all the way to xclbin, because the value of options.emitCtrlPkt over here in the code when I print it is 17, even though the default value is false (0).

I don't know where the bug is, iree-amd-aie, iree, or the clang C++ compiler I'm using. I've spent some time trying to find some invalid code, but without any success. The change in this PR fixes my problem, although it's definitely just a workaround for another deeper issue (initializing with {false} instead of = false should be valid afaik).

The only nice thing about this PR is that IREE initializes options with = false instead of {false}, so at least we're aligning with IREE.

[jtuyls]

Euh, this shouldn't make a difference afaik..

Not sure about IREE, and in most cases it doesn't matter too much, but list initialization is preferred by the developer of C++ and it should be the version that always works: https://stackoverflow.com/questions/18222926/what-are-the-advantages-of-list-initialization-using-curly-braces?rq=1