wifi: ath10k: Remove unused struct ath10k_htc_frame

struct ath10k_htc_frame is unused, and since it illogically contains
two consecutive flexible arrays, it could never be used, so remove it.

No functional changes, compile tested only.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20231103-ath10k_htc_frame-v1-1-ff00b38a9630@quicinc.com

drivers/net/wireless/ath/ath10k/htc.h

@@ -253,19 +253,6 @@ struct ath10k_htc_record {
 	};
 } __packed __aligned(4);
 
-/*
- * note: the trailer offset is dynamic depending
- * on payload length. this is only a struct layout draft
- */
-struct ath10k_htc_frame {
-	struct ath10k_htc_hdr hdr;
-	union {
-		struct ath10k_htc_msg msg;
-		u8 payload[0];
-	};
-	struct ath10k_htc_record trailer[0];
-} __packed __aligned(4);
-
 /*******************/
 /* Host-side stuff */
 /*******************/