remove unused IRC bot from openstack

this used to be labs-storage-wm,
likely used to check glusterfs,
but we don't use it anymore

and since it included role::echoirc
it would have been broken since
I6e5d832c92

instead of making another role
just delete it

Change-Id: I1c7dd567ecf7e10efde6ef4373121e057a62f86b