QtPrintSupport - Increase Cups required to 1.4

Change the minimum required version of CUPS to be 1.4, which has been
available in most distros since 2009.  Note this is only available in
RHEL 6 and later, RHEL 5 will no longer be supported for printing.

[ChangeLog][QtPrintSupport] CUPS 1.4 is now required for print support
on Linux and other *nix platforms.

Change-Id: Id9c4c748be6436ccc995da08ff6bb3eeef08c35a
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

config.tests/unix/cups/cups.cpp

@@ -43,7 +43,7 @@
 
 int main(int, char **)
 {
-    cups_dest_t *d;
-    cupsGetDests(&d);
+    // CUPS 1.4 test
+    cupsGetNamedDest(CUPS_HTTP_DEFAULT, NULL, NULL);
     return 0;
 }