Add support for Oracle Linux 7 and later.

Most of the changes revolves around using MySQL rather than MariaDB,
plus enabling the addon repos on public-yum.oracle.com.
The patch just touch the areas where there is a divergence between the
Fedora and Oracle distributions and in all other cases the is_fedora
will result in the correct decision to be made and left as is.

Collapsed the is_suse and is_oraclelinux into a single check in
configure_database_mysql and cleanup_database_mysql

Added Oracle Linux to MAINTAINERS.rst

Rather than duplicating most of the Redhat version check code, added
a check in the block to do the determination if it is Oracle Linux

Change-Id: I5f1f15106329eec67aa008b17847fa44863f243f

lib/databases/mysql

@@ -16,7 +16,7 @@ register_database mysql
 
 # Linux distros, thank you for being incredibly consistent
 MYSQL=mysql
-if is_fedora; then
+if is_fedora && ! is_oraclelinux; then
     MYSQL=mariadb
 fi
 
@@ -32,12 +32,12 @@ function cleanup_database_mysql {
         sudo rm -rf /var/lib/mysql
         sudo rm -rf /etc/mysql
         return
+    elif is_suse || is_oraclelinux; then
+        uninstall_package mysql-community-server
+        sudo rm -rf /var/lib/mysql
     elif is_fedora; then
         uninstall_package mariadb-server
         sudo rm -rf /var/lib/mysql
-    elif is_suse; then
-        uninstall_package mysql-community-server
-        sudo rm -rf /var/lib/mysql
     else
         return
     fi
@@ -56,12 +56,12 @@ function configure_database_mysql {
     if is_ubuntu; then
         my_conf=/etc/mysql/my.cnf
         mysql=mysql
+    elif is_suse || is_oraclelinux; then
+        my_conf=/etc/my.cnf
+        mysql=mysql
     elif is_fedora; then
         mysql=mariadb
         my_conf=/etc/my.cnf
-    elif is_suse; then
-        my_conf=/etc/my.cnf
-        mysql=mysql
     else
         exit_distro_not_supported "mysql configuration"
     fi
@@ -140,14 +140,14 @@ EOF
         chmod 0600 $HOME/.my.cnf
     fi
     # Install mysql-server
-    if is_fedora; then
-        install_package mariadb-server
-    elif is_ubuntu; then
-        install_package mysql-server
-    elif is_suse; then
+    if is_suse || is_oraclelinux; then
         if ! is_package_installed mariadb; then
             install_package mysql-community-server
         fi
+    elif is_fedora; then
+        install_package mariadb-server
+    elif is_ubuntu; then
+        install_package mysql-server
     else
         exit_distro_not_supported "mysql installation"
     fi