Comment # 59 on bug 954783 from Takashi Iwai

initramfs should be named as initrd for SUSE.  Maybe instead of regenerated
initrd, you could rename initrd-4.1-x86.img as initrd-4.1-x86_64.  And, instead
of manual grub2-mkconfig, you can try update-bootloader script, e.g.:

  update-bootloader --add --image /boot/vmlinuz-xxx --initrd /boot/initrd-xxx
  update-bootloader --refresh

The module files themselves have no relation of the path, so it shouldn't
matter whether /lib/modules or /lib64/modules.  It's at most the modprobe which
matters.