tmem: fixup 2010 cleanup patch that breaks tmem save/restore

tmem: fixup 2010 cleanup patch that breaks tmem save/restore

20918:a3fa6d444b25 "Fix domain reference leaks" (in Feb 2010, by Jan)
does some cleanup in addition to the leak fixes.  Unfortunately, that
cleanup inadvertently resulted in an incorrect fallthrough in a switch
statement which breaks tmem save/restore.

That broken patch was apparently applied to 4.0-testing and 4.1-testing
so those are broken as well.

What is the process now for requesting back-patches to 4.0 and 4.1?

(Side note: This does not by itself entirely fix save/restore in 4.2.)

Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Committed-by: Jan Beulich <jbeulich@suse.com>