staging: vchiq_core: Bulk waiter should not piggy back on bulk userdata

staging: vchiq_core: Bulk waiter should not piggy back on bulk userdata

Currently, struct bulk_waiter is allocated for VCHIQ_BULK_MODE_BLOCKING
bulk transfer and its pointer is assigned to vchiq_bulk->userdata. Avoid
this kind of piggybacking and introduce a dedicate 'waiter' member in
struct vchiq_bulk.

The 'userdata' is meant for VCHIQ_BULK_MODE_CALLBACK mode, to pass user
specified parameter to the actual callback function.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Link: https://lore.kernel.org/r/20241023110406.885199-3-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>