Strip newline characters when reading .config
Replace and-or construct with if-else
Tell cpio to chown root:root the initramfs contents
Use NUL to separate file paths fed to cpio
Support no initramfs compression (self._m_comprIrf = None)
Include directories in the paths passed to cpio

Something must have changed, either in Linux or in cpio, so that folders
missing from the cpio archive result in a cpio archive that cannot be
loaded. This change makes sure that folders are included.