This reverts commit 55b9706b, which is obsoleted
by b4f666f2 "Bump Xcode baseline to 9.3".

Change-Id: Id2240351ed9495e311d55887b8e34f2aa776ae06
Reviewed-on: https://gerrit.libreoffice.org/63896
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>