LU-16333 osc: page fault in osc_release_bounce_pages()

LU-16333 osc: page fault in osc_release_bounce_pages()

pga[i] can be uninitialized. It happens after following
code path in osc_build_rpc():

        OBD_SLAB_ALLOC_PTR_GFP(oa, osc_obdo_kmem, GFP_NOFS);
        if (oa == NULL)
                GOTO(out, rc = -ENOMEM);

Fixes: a9ed5b149646 ("LU-12275 sec: encryption for write path")
HPE-bug-id: LUS-10991
Signed-off-by: Andriy Skulysh <andriy.skulysh@hpe.com>
Reviewed-by: Alexander Zarochentsev <alexander.zarochentsev@hpe.com>
Reviewed-by: Alexander Boyko <c17825@cray.com>
Change-Id: I7e21cb9ab69f0bce9c1bdb53a4b0ac7a673887cc
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/49210
Reviewed-by: Sebastien Buisson <sbuisson@ddn.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Alexander Boyko <alexander.boyko@hpe.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>