The font database uses UIKit symbols on all UIKit platforms and thus it
must be linked to. Also, limit the missing CoreText.h workaround so
that it is not applied for versions of Xcode where the bug is fixed.
Change-Id: Ia2a94baba6b0df618604a0bc3092fbd2a48d5aea
Reviewed-by: Jake Petroules <jake.petroules@qt.io>
