If a proc (e.g., a tool) wants to fetch a piece of job-level data
for a namespace other than their own, then it is likely that the
proc won't already have a copy of that data. If they have done
a PMIx_Connect or PMIx_Group_construct operation that included
the other namespace, then they should have it - but otherwise,
they likely don't. This is normally the case for tools, as an
example.

Ensure we flow the request up to the server for processing. Given
that it is job-level info (i.e., it is a request for a reserved
key), then we only want to flow thru the fetch process once. If
it is found, then no need to search further in other scopes - if
it isn't found in the initial "internal" scope, then it definitely
won't be found on some other scope.

Signed-off-by: Ralph Castain <rhc@pmix.org>
(cherry picked from commit 1933e42)