gitweb: Strip trailing slashes from $path in git_get_hash_by_path

It also removes unused local variable $tree

Signed-off-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

gitweb/gitweb.perl

@@ -710,7 +710,7 @@ sub git_get_hash_by_path {
 	my $path = shift || return undef;
 	my $type = shift;
 
-	my $tree = $base;
+	$path =~ s,/+$,,;
 
 	open my $fd, "-|", git_cmd(), "ls-tree", $base, "--", $path
 		or die_error(undef, "Open git-ls-tree failed");