Xcode: Fix erroneous MACOSX_BUNDLE link

Refactoring in commit a2cfa2da4f (GenEx/LINK_LIBRARY: Add features for
framework support on Apple, 2022-02-10, v3.24.0-rc1~661^2) accidentally
removed a `GetParentDirectory` call.  Restore it.

Fixes: #23891
6 files changed