Fix build break in osp-installer.

Fix build break in osp-installer.

This commit adds mockups for functions required by osp-installer:
* perm_app_set_privilege
* perm_app_id_from_socket
* perm_app_install
* perm_app_uninstall
* perm_app_enable_permissions
* perm_app_disable_permissions
* perm_app_revoke_permissions
* perm_app_reset_permissions
* perm_app_setup_path
* app_setup_path
* perm_app_add_friend
* perm_add_api_feature

Change-Id: I1b9abf5f7c05379089741b288240ebc630326fe4
Signed-off-by: Bartlomiej Grzelewski <b.grzelewski@samsung.com>