Installer/Mac: don't add fancy stuff into the installer app name.

The file name pattern that is used for win/lin should only be used for
the resulting disk image, not the installer app itself

Change-Id: Ia0b41fd379faf093af71dc526f32a768552d5e2f
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

qtcreator.pro

@@ -58,7 +58,8 @@ else: PLATFORM = "unknown"
 
 PATTERN = $${PLATFORM}$(INSTALL_EDITION)-$${QTCREATOR_VERSION}$(INSTALL_POSTFIX)
 
-INSTALLER_NAME = "qt-creator-$${PATTERN}"
+macx:INSTALLER_NAME = "qt-creator-$${QTCREATOR_VERSION}"
+else:INSTALLER_NAME = "qt-creator-$${PATTERN}"
 
 macx {
     APPBUNDLE = "$$OUT_PWD/bin/Qt Creator.app"