distro/rpm: remove useless %systemd_post

%system_post creates a preset, which we don't use (but could perhaps
replace the symlink for kresd.target).
21 jobs for deb-restart-kres-gc in 88 minutes and 43 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #353172
amd64 linux docker
archive

00:01:39

 
  Deploy
passed #353173
respdiff
obs:trigger

00:00:15

 
  Deploy Test
passed #353174
respdiff delayed
obs:build:all

01:09:22

passed #353262
respdiff delayed
obs:centos7:x86_64

00:03:38

passed #353268
respdiff delayed
obs:debian10:x86_64

00:10:16

passed #353267
respdiff delayed
obs:debian9:x86_64

00:11:46

passed #353269
respdiff delayed
obs:fedora30:x86_64

00:08:45

passed #353270
respdiff delayed
obs:fedora31:x86_64

00:06:45

passed #353271
respdiff delayed
obs:leap15:x86_64

00:12:45

passed #353272
respdiff delayed
obs:ubuntu1604:x86_64

00:13:44

passed #353273
respdiff delayed
obs:ubuntu1804:x86_64

00:13:44

passed #353274
respdiff delayed
obs:ubuntu1910:x86_64

00:13:44

failed #353175
respdiff delayed
obs:centos7:x86_64

01:09:21

failed #353177
respdiff delayed
obs:debian10:x86_64

01:09:21

failed #353176
respdiff delayed
obs:debian9:x86_64

01:09:21

failed #353178
respdiff delayed
obs:fedora30:x86_64

01:09:20

failed #353179
respdiff delayed
obs:fedora31:x86_64

01:09:21

failed #353180
respdiff delayed
obs:leap15:x86_64

01:09:20

failed #353181
respdiff delayed
obs:ubuntu1604:x86_64

01:09:20

failed #353182
respdiff delayed
obs:ubuntu1804:x86_64

03:05:00

failed #353183
respdiff delayed
obs:ubuntu1910:x86_64

01:09:20