Add new qmp json is not setting command errp

[bambooza]

I am attempting to add a new json file for qmp.  My issue is that errp is null so when I call error_setg qemu crashes.

Specifically 

QEMU: F0000 00:00:1699907518.054094 2802908 logging.cc:57] assert.h assertion failed at qemu/util/error.c:59 in void error_setv(Error **, const char *, int, const char *, ErrorClass, const char *, struct __va_list_tag *, const char *): *errp == NULL

I am not sure what I'm missing.  The generated files for command, event, types, visit and view are created.  

The function gets called and the passed in value is correctly populated just errp is null.