ui/cocoa.m: Drop old macOS-10.12-and-earlier compat ifdefs

We only support the most recent two versions of macOS (currently
macOS 13 Ventura and macOS 14 Sonoma), and our ui/cocoa.m code
already assumes at least macOS 12 Monterey or better, because it
uses NSScreen safeAreaInsets, which is 12.0-or-newer.

Remove the ifdefs that were providing backwards compatibility
for building on 10.12 and newer.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
1 file changed