scsi: hptiop: Replace one-element array with flexible-array member in struct hpt_iop_...

scsi: hptiop: Replace one-element array with flexible-array member in struct hpt_iop_request_ioctl_command()

One-element arrays are deprecated, and we are replacing them with flexible
array members instead. So, replace one-element array with flexible-array
member in struct hpt_iop_request_ioctl_command.

Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/205
Link: https://lore.kernel.org/r/YyyUvuId7dAZadej@work
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>