[ARM] pxa: define "struct ssp_device" and add ssp_request()/ssp_free()

1. define "struct ssp_device" for SSP information, which is requested
   and released by function ssp_request()/ssp_free()

2. modify the ssp_init() and ssp_exit() to use the interface

Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2 files changed