Is __OPENTRANSPORTPROVIDERS__ (still) needed

...to be set before including Carbon/Carbon.h?  Was originally introduced with
c34f2e30bbad1a6b92308d0daabe413bd1bc161b "INTEGRATION: CWS pj51: #i61959# patch
applied", but might just be cargo cult these days.

Change-Id: I20cdc938d28e075614f6711a06ab785700833aff
Reviewed-on: https://gerrit.libreoffice.org/24293
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
diff --git a/sal/osl/unx/system.hxx b/sal/osl/unx/system.hxx
index bd3d2c4..ec7fa48 100644
--- a/sal/osl/unx/system.hxx
+++ b/sal/osl/unx/system.hxx
@@ -197,7 +197,6 @@
#endif

#ifdef MACOSX
#define __OPENTRANSPORTPROVIDERS__ // these are already defined
#define TimeValue CFTimeValue      // Do not conflict with TimeValue in sal/inc/osl/time.h
#include <Carbon/Carbon.h>
#undef TimeValue