cvsserver: suppress warnings

This patch defines $state->{prependdir} as the empty string, so that
quite a few warnings are avoided.

Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Acked-by: Martin Langhoff <martin@catalyst.net.nz>
Signed-off-by: Junio C Hamano <junkio@cox.net>

git-cvsserver.perl

@@ -81,7 +81,7 @@
 
 # $state holds all the bits of information the clients sends us that could
 # potentially be useful when it comes to actually _doing_ something.
-my $state = {};
+my $state = { prependdir => '' };
 $log->info("--------------- STARTING -----------------");
 
 my $TEMP_DIR = tempdir( CLEANUP => 1 );