driver_list: unbreak list of builtin drivers for LTO configurations

driver_list: unbreak list of builtin drivers for LTO configurations

Check for the availability of the "no_reorder" linker attribute, which
keeps the list of builtin drivers in shape on LTO enabled build setups.
Keep backwards compatibility for platforms which lack support for the
"no_reorder" attribute. Phrase the implementation such that other
keywords as well as user provided external specs are possible.

This resolves bug #1433.

Submitted-By: Ivan Mironov <redacted>