git-svn: allow SVN:: lib users to track the root of the repository (again)

I broke this again in 747fa12cef73b6ca04fffaddaad7326cf546cdea.

Thanks to merlyn for pointing this out to me on IRC.

Signed-off-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/git-svn.perl b/git-svn.perl
index 0a47b1f..de4e74a 100755
--- a/git-svn.perl
+++ b/git-svn.perl
@@ -2919,8 +2919,12 @@
 	my $p = $SVN->{svn_path};
 	foreach my $f (keys %$paths) {
 		my $m = $paths->{$f}->action();
-		$f =~ s#^/\Q$p\E/##;
-		next if $f =~ m#^/#;
+		if (length $p) {
+			$f =~ s#^/\Q$p\E/##;
+			next if $f =~ m#^/#;
+		} else {
+			$f =~ s#^/##;
+		}
 		if ($m =~ /^[DR]$/) {
 			print "\t$m\t$f\n" unless $_q;
 			process_rm($gui, $last_commit, $f);