Description of problem:
The recent reworking of mkinitrd to better support NFS root broke root on LVM
(or rather root without LABEL= in /etc/fstab), since rootopts is not edited
properly so as to contain ro (unless /etc/fstab is supposed to contain it
explicitly; in my case it does not)

Version-Release number of selected component (if applicable):
mkinitrd-5.0.36-1

How reproducible:
Every time

Steps to Reproduce:
1.List / in /etc/fstab without LABEL= and without ro in the mount options
2.Run mkinitrd
3.Verify that initrd.img's init script doesn't mount root with ro
4.Boot into it
  
Actual results:
fsck fails to check the root filesystem because it's already mounted read-write

Expected results:
It should have been mounted read-only

Additional info:
The attached patch uses an uglyish shell idiom to avoid duplicating the sed command.

This is fixed in 5.0.37-1.