Comment # 3 on bug 958562 from Takashi Iwai

This seems missing indeed.  I guess the same issue is found on SLE12, too.

And, I think this is a generic problem.  Now lots of packages are using
%regenerate_initrd_* macros, and they also don't have this prereq.

On FACTORY,

% grep -l regenerate_initrd */*.spec
biosdevname/biosdevname.spec
btrfsprogs/btrfsprogs.spec
coreutils/coreutils.spec
coreutils/coreutils-testsuite.spec
cryptsetup/cryptsetup.spec
dmraid/dmraid.spec
dracut/dracut.spec
haveged/haveged.spec
kbd/kbd.spec
kernel-firmware/kernel-firmware.spec
kexec-tools/kexec-tools.spec
kmod/kmod.spec
lvm2/lvm2.spec
mdadm/mdadm.spec
multipath-tools/multipath-tools.spec
open-iscsi/open-iscsi.spec
plymouth/plymouth.spec
systemd/systemd-mini.spec
systemd/systemd.spec
ucode-intel/ucode-intel.spec

Maybe it's worth for creating a new macro to be more clear for requirements?