Fix instance_system_metadata deleted columns

Migration 153 adds instance_type data to sys_meta, but creates entries
with the default value of deleted.. which is NULL.  This means these
entries do not get pulled in on a join when querying an instance, as
there is a condition of deleted=0.

This converts 'deleted' NULL entries to be 0.

Fixes bug 1147839

Change-Id: I3caf92b3992b22089a2653c2e7220585d616a102
Merge "Fix instance_system_metadata deleted columns"