One-element arrays (and multi-element arrays being treated as dynamically
sized) are deprecated[1] and are being replaced with flexible array members
in support of the ongoing efforts to tighten the FORTIFY_SOURCE routines on
memcpy(), correctly instrument array indexing with UBSAN_BOUNDS, and to
globally enable -fstrict-flex-arrays=3.

Replace one-element arrays with flexible-array member in TW_Ioctl_Buf_Apache
and TW_Param_Apache, adjusting the explicit sizing calculations at the
same time.

This results in no differences in binary output.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays

Cc: Adam Radford <aradford@gmail.com>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230105004757.never.017-kees@kernel.orgSigned-off-by: Martin K. Petersen <martin.petersen@oracle.com>