staging: ks7010: Remove unused 'struct hostif_sleep_confirm_t'.

'struct hostif_sleep_confirm_t' is not used in this driver. Remove 'struct
hostif_sleep_confirm_t'.

Signed-off-by: Quytelda Kahja <quytelda@tamalin.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>