Fatal error when try to enable Audit filter logging module on php less than 5.5

When try to enable the Audit filter logging module on php less than 5.5 version the fatal error is appear:
"Fatal error: Can't use function return value in write context in audit_log/modules/audit_log_filter/audit_log_filter.module on line 11"

From empty() function description:
"Note:
Prior to PHP 5.5, empty() only supports variables; anything else will result in a parse error. In other words, the following will not work: empty(trim($name)). Instead, use trim($name) == false."

Here is a patch which will prevent this error.