media: venus: hfi_cmds: Use struct_size() helper

Prefer struct_size() over open-coded versions of idiom:

sizeof(struct-with-flex-array) + sizeof(typeof-flex-array-elements) * count

where count is the max number of items the flexible array is supposed to
contain.

Link: https://github.com/KSPP/linux/issues/160Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Stanimir Varbanov <stanimir.k.varbanov@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/qcom/venus/hfi_cmds.c

@@ -209,8 +209,8 @@ int pkt_session_set_buffers(struct hfi_session_set_buffers_pkt *pkt,
 		}
 	} else {
 		pkt->extradata_size = 0;
-		pkt->shdr.hdr.size = sizeof(*pkt) +
-			bd->num_buffers * sizeof(u32);
+		pkt->shdr.hdr.size = struct_size(pkt, buffer_info,
+						 bd->num_buffers);
 		for (i = 0; i < pkt->num_buffers; i++)
 			pkt->buffer_info[i] = bd->device_addr;
 	}
@@ -251,8 +251,8 @@ int pkt_session_unset_buffers(struct hfi_session_release_buffer_pkt *pkt,
 
 		pkt->extradata_size = 0;
 		pkt->shdr.hdr.size =
-				sizeof(struct hfi_session_set_buffers_pkt) +
-				bd->num_buffers * sizeof(u32);
+			struct_size((struct hfi_session_set_buffers_pkt *)0,
+				    buffer_info, bd->num_buffers);
 	}
 
 	pkt->response_req = bd->response_required;