libata: update libata LLDs to use devres

Update libata LLDs to use devres.  Core layer is already converted to
support managed LLDs.  This patch simplifies initialization and fixes
many resource related bugs in init failure and detach path.  For
example, all converted drivers now handle ata_device_add() failure
gracefully without excessive resource rollback code.

As most resources are released automatically on driver detach, many
drivers don't need or can do with much simpler ->{port|host}_stop().
In general, stop callbacks are need iff port or host needs to be given
commands to shut it down.  Note that freezing is enough in many cases
and ports are automatically frozen before being detached.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>