ide: use the dma safe check for REQ_TYPE_ATA_PC

This uses the dma safe check for REQ_TYPE_ATA_PC. The dma safe check
is used for only sg requests but it should be used for other non fs
commands.

This uses blk_queue_update_dma_pad to make the intention clear though
ide don't use the blk APIs so it doesn't change anything.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>