xfs: place intent recovery under NOFS allocation context

When recovery starts processing intents, all of the initial intent
allocations are done outside of transaction contexts. That means
they need to specifically use GFP_NOFS as we do not want memory
reclaim to attempt to run direct reclaim of filesystem objects while
we have lots of objects added into deferred operations.

Rather than use GFP_NOFS for these specific allocations, just place
the entire intent recovery process under NOFS context and we can
then just use GFP_KERNEL for these allocations.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>