Gain MySQL compatibility by allowing table aliases in a single
table statement.

This now supports the syntax of:

DELETE [delete_opts] FROM tbl_name [[AS] tbl_alias] [PARTITION (partition_name [, partition_name] ...)] ....

The delete.test is from MySQL commit 1a72b69778a9791be44525501960b08856833b8d
/ Change-Id: Iac3a2b5ed993f65b7f91acdfd60013c2344db5c0.

Co-Author: Gleb Shchepa <gleb.shchepa@oracle.com> (for delete.test)

Reviewed by Igor Babaev (igor@mariadb.com)