Fix style.
Merge topic 'minor-cleanup' into next

a45d3ff Fix style.
Export: Skip INTERFACE libraries when generating -config files.

The properties object has just been created, so is always empty,
which means the if block is never entered. The following lines do
not have any effect because an INTERFACE library has no LOCATION.
At the end, no code is generated for INTERFACE libraries in
config-specific exported files, so skip them early.
Merge topic 'minor-cleanup' into next

b51b6e9 Export: Skip INTERFACE libraries when generating -config files.