rapide: set hwif->chipset

hwif->chipset should be set if the hwif is claimed by host driver.

Cc: Russell King <rmk@arm.linux.org.uk>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>