[PATCH] wine.inf: Enable Light theme by default.

[Esme Povirk (she/they)]

I don't know if this is important, but Wine Mono has a few tests of
exact sizes that break with this theme.

For example:
x86_64.MonoTests.System.Windows.Forms.ToolStripTests:Constructor failed:
  A12
  Expected: {X=7,Y=0,Width=92,Height=25}
  But was:  {X=9,Y=0,Width=90,Height=25}

Corresponding source code:
https://github.com/madewokherd/mono/blob/56d140974e5fa56d83d29c41e933ff11cd306439/mcs/class/System.Windows.Forms/Test/System.Windows.Forms/ToolStripTest.cs#L60

I haven't been able to figure out how exactly the theme affects this
calculation. It's possible there's a bug in Wine's uxtheme, Mono, or
winforms code that only gets called when visual styles are enabled.

If this is determined by the theme and Windows has been keeping it
constant, that's probably for a reason, but I don't have an easy way
to test with XP, Vista, and 7 themes.