SPARC64: vds_blk_rw() does not handle drives with q->limits.chunk_sectors > 0

SPARC64: vds_blk_rw() does not handle drives with q->limits.chunk_sectors > 0

Drives with q->limits.chunk_sectors > 0 are not properly handled by
vds_blk_rw(). Drives such as NVME set chunk_sectors to indicate a performance
boundary (see call to blk_queue_chunk_sectors() in nvme_alloc_ns()). Currently,
when vds_blk_rw() calls bio_add_page() and the chunk_sectors boundary would be
crossed, bio_add_page() returns zero and vds_blk_rw() fails with -EIO.

The proposed fix now adds an additional check to vds_blk_rw() when
bio_add_page() returns zero that checks for bio->bi_iter.bi_size != 0. If
bi_size != 0, it indicates that a page or pages have been successfully added by
bio_add_page(). When this added condition has been hit, exit the for loop in
vds_blk_rw() and submit the outstanding IOs and continue.

Signed-off-by: George Kennedy <george.kennedy@oracle.com>
Reviewed-By: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Reviewed-By: Liam Merwick <Liam.Merwick@oracle.com>
Orabug: 25373818
Signed-off-by: Allen Pais <allen.pais@oracle.com>