xfs: fix simple problems with log intent recovery

Dave and I were talking about various issues that he had discovered
while wandering through the log recovery code, and then I started taking
a closer look and found bugs aplenty.  This first series is a very short
one that cleans up some low hanging fruit I found -- the most serious is
that we don't log new intent items created in the process of recovering
intent items that we found in the log, which breaks the recoverability
of log chains.  The other thing I found was that bmap intent recovery
didn't attach dquots, which could lead to incorrect quota accounting if
the BUI recovery caused a bmap btree shape change.