dma-mapping: mark dma_sync_single and dma_sync_sg as deprecated

dma_sync_single() and dma_sync_sg() have been described as "Backwards
compat, remove in 2.7.x" for a long time (since 2.6.5).

This marks dma_sync_single() and dma_sync_sg() as deprecated so the users
get notified before removing them.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>