On CentOS/Fedora, dracut is configured to write the initrd to /boot/initramfs-$KERNEL_VERSION...img so let's check for that as well if no initrds were supplied.
On CentOS/Fedora, dracut is configured to write the initrd to /boot/initramfs-$KERNEL_VERSION...img so let's check for that as well if no initrds were supplied.