gitweb: git_get_project_config requires only $git_dir, not also $project

Fix overeager early return in git_get_project_config, introduced in 9be3614
(gitweb: Fix project-specific feature override behavior, 2010-03-01).  When
git_get_project_config is called from projects list page via
git_get_project_owner($path) etc., it is called with $git_dir defined (in
git_get_project_owner($path) etc.), but $project variable is not defined.
git_get_project_config doesn't use $project variable anyway.

Reported-by: Tobias Heinlein <keytoaster@gentoo.org>
Signed-off-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

gitweb/gitweb.perl

@@ -2209,8 +2209,7 @@ sub config_to_multi {
 sub git_get_project_config {
 	my ($key, $type) = @_;
 
-	# do we have project
-	return unless (defined $project && defined $git_dir);
+	return unless defined $git_dir;
 
 	# key sanity check
 	return unless ($key);