W1: OMAP HDQ1W: use runtime PM

Convert the OMAP HDQ driver to use runtime PM.  Compile- and boot-tested,
but not tested in actual use.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Tested-by: NeilBrown <neilb@suse.de>