ntfs-3g-ntfsprogs: Fix runtime dependency for development package

The -dev has a runtime dependency against ${PN} which is empty; we
allow it to be empty to satisfy the dependency instead of mangingling
the -dev dependencies.

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>