Fix failing PLC build when building freshly created project that use default libraries blocks. When controller loads libraries according to attibutes in project files (BeremizRoot/Enable_{libname}_Library), use known default if attribute is missing.

<?xml version='1.0' encoding='utf-8'?>
<MemoryArea xmlns:xsd="http://www.w3.org/2001/XMLSchema" MemoryAreaType="04 - Input Registers"/>