+++ This bug was initially created as a clone of Bug #1391521 +++

Description of problem:

In Fedora we have this rule for mysql directories:
  /var/lib/mysql(-files|-keyring)?(/.*)?    mysqld_db_t

In RHEL we only have:
  /var/lib/mysql(/.*)?                      mysqld_db_t

For RHSCL packages (rh-mysql56 specifically) we now started to use /var/opt/rh/rh-mysql56/lib/mysql-files (because of bz #1384962) and we also define this rule:
  /var/opt/rh/rh-mysql56 = /var (using semanage fcontext -a -e ...)

Since selinux's "equality" cannot be defined twice for given directory, we cannot define something like the following in mysql packge:
  /var/lib/mysql = /var/lib/mysql-files
or something like
  /var/opt/rh/rh-mysql56/lib/mysql-files = /var/lib/mysql

So I think we should change the definition in selinux-policy to be the same as in Fedora:
  /var/lib/mysql(-files|-keyring)?(/.*)?    mysqld_db_t

This would help in all packages we ship, so it wouldn't require us to fix particular packages.

Version-Release number of selected component (if applicable):
selinux-policy-3.13.1-102.el7.noarch

Steps to Reproduce:
1. ls -lZd /var/opt/rh/rh-mysql56/lib/mysql-files

Actual results:
drwxr-x---. mysql mysql system_u:object_r:var_lib_t:s0   /var/opt/rh/rh-mysql56/lib/mysql-files/

Expected results:
drwxr-x---. mysql mysql system_u:object_r:mysqld_db_t:s0   /var/opt/rh/rh-mysql56/lib/mysql-files/