ext4: avoid updating the superblock on a r/o mount if not needed
JIRA: https://issues.redhat.com/browse/RHEL-7953 Signed-off-by: Pavel Reichl preichl@redhat.com
JIRA: https://issues.redhat.com/browse/RHEL-7953 Signed-off-by: Pavel Reichl preichl@redhat.com