Comment # 1 on bug 1057142 from Ladislav Slez�k

Unfortunately RPi1 is not supported by YaST. YaST supports only aarch64 EFI
based boards. 

On RPi1 you have configure booting manually. You can find some booting hints at
https://en.opensuse.org/HCL:Raspberry_Pi#Installing_the_openSUSE_Tumbleweed_image