waylandloginmanager: Fix the launching of the debug terminal

git-svn-id: https://rebeccablackos.svn.sourceforge.net/svnroot/rebeccablackos@2914 56e3d1a8-0179-4092-b3e2-9fbbcda0c0a9
The Waylandloginmanager runs "exposed" on TTY 63, so it can display fallback text "dialogs" when Weston fails. If someone switched to tty 63, and presssed ctrl+c the user would be able to kill the waylandloginmanager. Intercept CTRL+C and do nothing.

git-svn-id: https://rebeccablackos.svn.sourceforge.net/svnroot/rebeccablackos@2915 56e3d1a8-0179-4092-b3e2-9fbbcda0c0a9