scsi: aacraid: union aac_init: Replace 1-element array with flexible array

Replace the deprecated[1] use of a 1-element array in union aac_init with a
modern flexible array.

Additionally add __counted_by annotation since rrq is only ever accessed
after rr_queue_count has been set (with the same value used to control the
loop):

                init->r8.rr_queue_count = cpu_to_le32(dev->max_msix);
		...
                for (i = 0; i < dev->max_msix; i++) {
                        addr = (u64)dev->host_rrq_pa + dev->vector_cap * i *
                                        sizeof(u32);
                        init->r8.rrq[i].host_addr_high = cpu_to_le32(
                                                upper_32_bits(addr));

No binary differences are present after this conversion.

Link: KSPP#79 [1]
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://lore.kernel.org/r/20240711174815.work.689-kees@kernel.org
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Author: kees

drivers/scsi/aacraid/aacraid.h

@@ -873,7 +873,7 @@ union aac_init
 			__le16	element_count;
 			__le16	comp_thresh;
 			__le16	unused;
-		} rrq[1];		/* up to 64 RRQ addresses */
+		} rrq[] __counted_by_le(rr_queue_count); /* up to 64 RRQ addresses */
 	} r8;
 };
 

drivers/scsi/aacraid/src.c

@@ -410,7 +410,7 @@ static void aac_src_start_adapter(struct aac_dev *dev)
 			lower_32_bits(dev->init_pa),
 			upper_32_bits(dev->init_pa),
 			sizeof(struct _r8) +
-			(AAC_MAX_HRRQ - 1) * sizeof(struct _rrq),
+			AAC_MAX_HRRQ * sizeof(struct _rrq),
 			0, 0, 0, NULL, NULL, NULL, NULL, NULL);
 	} else {
 		init->r7.host_elapsed_seconds =