SIC QPrintSupport: Remove unused PPK_SuppressSystemPrintStatus

Print Engine key PPK_SuppressSystemPrintStatus was added in Qt4.1
for Cocoa dialog to suppress the progress dialog.  In Qt5 all cocoa
code has been removed and this key is now unused.

Change-Id: I3a91e9651e16f81611a9a736163f76acf9f20096
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>

dist/changes-5.0.0

@@ -325,6 +325,8 @@ information about a particular change.
 
 - QThread::terminated() has been removed, since its emission cannot be guaranteed.
 
+- QPrintEngine - Removed the PPK_SuppressSystemPrintStatus key as no longer used.
+
 ****************************************************************************
 *                           General                                        *
 ****************************************************************************

src/plugins/platforms/cocoa/qprintengine_mac.mm

@@ -642,8 +642,6 @@ void QMacPrintEngine::setProperty(PrintEnginePropertyKey key, const QVariant &va
             d->state = QPrinter::Idle;
         }
         break; }
-    case PPK_SuppressSystemPrintStatus:
-        break;
     case PPK_CustomPaperSize:
     {
         PMOrientation orientation;

src/printsupport/kernel/qprintengine.h

@@ -78,7 +78,6 @@ public:
 
         PPK_WindowsPageSize,
         PPK_FontEmbedding,
-        PPK_SuppressSystemPrintStatus,
 
         PPK_Duplex,
 

src/printsupport/kernel/qprinter.cpp

@@ -1974,10 +1974,6 @@ QPrinter::PrintRange QPrinter::printRange() const
     \value PPK_SupportedResolutions A list of integer QVariants
     describing the set of supported resolutions that the printer has.
 
-    \value PPK_SuppressSystemPrintStatus Suppress the built-in dialog for showing
-    printing progress. As of 4.1 this only has effect on Mac OS X where, by default,
-    a status dialog is shown.
-
     \value PPK_WindowsPageSize An integer specifying a DM_PAPER entry
     on Windows.