staging: gpib: Add bit and byte padding to ioctl structs

Ensure that all structs have a size that is an integral mutliple
of 32 bits.

Change trailing single bit field to __u32 in gpib_open_dev_ioctl
Add byte padding to  gpib_serial_poll_ioctl and gpib_request_service2
Add bit padding to gpib_board_info_ioctl and gpib_ppoll_config_ioctl

Signed-off-by: Dave Penkler <dpenkler@gmail.com>
Link: https://lore.kernel.org/r/20250603184320.30594-5-dpenkler@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>