BUG #16014: how to modify column ev_action of pg_rewrite

The following bug has been logged on the website:

Bug reference:      16014
Logged by:          DamionZ Zhao
Email address:      zhq651@126.com
PostgreSQL version: 11.4
Operating system:   linux
Description:

typedef enum CmdType
{
    CMD_UNKNOWN,
    CMD_SELECT,                    /* select stmt */
    CMD_UPDATE,                    /* update stmt */
    CMD_INSERT,                    /* insert stmt */
    CMD_DELETE,
    CMD_MERGE,                  /* merge stmt */
    CMD_UTILITY,                /* cmds like create, destroy, copy, vacuum,
                                 * etc. */
    CMD_NOTHING                    /* dummy command for instead nothing rules
                                 * with qual */
} CmdType;

we merge the patch "merge into" into my project, but you can see , CMD_MERGE
is not added in the end.
It leads to restore old version postgres data to new version postgres。
because CMD_UTILITY value has been  changed from 5 to 6, CMD_NOTHING has
been changed from 6 to 7.

so we want to modify pg_rewrite column :ev_action to resolve this problem.
Thanks very very much.  
Wait in a hurry！！！