[devhelp] Fix variable name for OS X build

[Aleksander Morgado <aleksm src gnome org>]

commit d1ead3ca637e0ea63fe783bd5d5152a7342d495d
Author: P. F. Chimento <philip chimento gmail com>
Date:   Wed Apr 6 23:28:22 2011 +0200

    Fix variable name for OS X build
    
    There was a syntax error in book_manager_add_from_xcode_docset,
    which broke the build on OS X.

 src/dh-book-manager.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/dh-book-manager.c b/src/dh-book-manager.c
index 4416d7f..aa1d605 100644
--- a/src/dh-book-manager.c
+++ b/src/dh-book-manager.c
@@ -563,7 +563,7 @@ book_manager_add_from_xcode_docset (DhBookManager *book_manager,
                                ".devhelp2") == 0) {
                         gchar *book_path;
 
-                        book_path = g_build_filename (path, name, NULL);
+                        book_path = g_build_filename (dir_path, name, NULL);
                         /* Add book from filepath */
                         book_manager_add_from_filepath (book_manager,
                                                         book_path);