fdo#46508 use ISCHECKFORPRODUCTUPDATES property for online update

ISCHECKFORPRODUCTUPDATES is a de-facto standard for enabling or
disabling Online Update feature. We had this property but it was
unused for a long time. Now LibreOffice can be installed with
msiexec /i LibO<version>.msi ISCHECKFORPRODUCTUPDATES=0 in order
to disable Online Update feature.

scp2/source/onlineupdate/file_onlineupdate.scp

@@ -27,13 +27,20 @@
 
 #include "macros.inc"
 
-SPECIAL_LIB_FILE( gid_File_Lib_Updchk , updchk )
+File gid_File_Lib_Updchk
+    BIN_FILE_BODY;
+    Styles = (PACKED);
+    Dir = gid_Brand_Dir_Program;
+    Name = "updchk.dll";
+    ComponentCondition="ISCHECKFORPRODUCTUPDATES=1";
+End
 
 File gid_File_Share_Registry_Onlineupdate_Xcd
     TXT_FILE_BODY;
     Styles = (PACKED);
     Dir = gid_Brand_Dir_Share_Registry;
     Name = "onlineupdate.xcd";
+    ComponentCondition="ISCHECKFORPRODUCTUPDATES=1";
 End
 
 #if defined LINUX || defined SOLARIS