<?php
/**
 * Prevent update notification for plugin
 * http://www.thecreativedev.com/disable-updates-for-specific-plugin-in-wordpress/
 * Place in theme functions.php or at bottom of wp-config.php
 */
function disable_plugin_updates( $value ) {
  if ( isset($value) && is_object($value) ) {
    if ( isset( $value->response['theme-my-login/theme-my-login.php'] ) ) {
      unset( $value->response['theme-my-login/theme-my-login.php'] );
    }
  }
  return $value;
}
add_filter( 'site_transient_update_plugins', 'disable_plugin_updates' );