better ppd detection

cron.pl

@@ -19,7 +19,7 @@ else
 # copy cron.pl into weekly cron
 copy("/opt/fi-printers/cron.pl", "/etc/cron.weekly/fi_printers_cron");
 
-my @files = glob( '/etc/cups/ppd/*.ppd' );
+my @files = glob( '/etc/cups/ppd/*fi.muni.ppd' );
 
 for my $item (@files) {
 	print "current $item\n";