Support MariaDB client library.
Support MariaDB client library.

When mariadb-client is already installed on a system, installing wpcli
currently requires to remove mariadb-client because mariadb-client and
mysql-client are in conflict.

gedex/wp-cli,rodrigoprimo/wp-cli,gitlost/wp-cli,boonebgorges/wp-cli,shawnhooper/wp-cli,rodrigoprimo/wp-cli,2ndkauboy/wp-cli,duncanjbrown/wp-cli,gedex/wp-cli,aaemnnosttv/wp-cli,miya0001/wp-cli,miya0001/wp-cli,trepmal/wp-cli,rodrigoprimo/wp-cli,GaryJones/wp-cli,boonebgorges/wp-cli,2ndkauboy/wp-cli,GaryJones/wp-cli,aaemnnosttv/wp-cli,gedex/wp-cli,gitlost/wp-cli,aaemnnosttv/wp-cli,duncanjbrown/wp-cli,GaryJones/wp-cli,trepmal/wp-cli,shawnhooper/wp-cli,trepmal/wp-cli,shawnhooper/wp-cli,boonebgorges/wp-cli,nyordanov/wp-cli,nyordanov/wp-cli,nyordanov/wp-cli,duncanjbrown/wp-cli,2ndkauboy/wp-cli,miya0001/wp-cli,gitlost/wp-cli