Revert "firewire: Annotate struct fw_iso_packet with __counted_by()"

This reverts commit d3155742.

The header_length field is byte unit, thus it can not express the number of
elements in header field. It seems that the argument for counted_by
attribute can have no arithmetic expression, therefore this commit just
reverts the issued commit.
Suggested-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20240725161648.130404-1-o-takashi@sakamocchi.jpSigned-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>

include/linux/firewire.h

@@ -462,9 +462,8 @@ struct fw_iso_packet {
 				/* rx: Sync bit, wait for matching sy	*/
 	u32 tag:2;		/* tx: Tag in packet header		*/
 	u32 sy:4;		/* tx: Sy in packet header		*/
-	u32 header_length:8;	/* Length of immediate header		*/
-				/* tx: Top of 1394 isoch. data_block    */
-	u32 header[] __counted_by(header_length);
+	u32 header_length:8;	/* Size of immediate header		*/
+	u32 header[];		/* tx: Top of 1394 isoch. data_block	*/
 };
 
 #define FW_ISO_CONTEXT_TRANSMIT			0