ath6kl: add prefix parameter to ath6kl_dbg_dump()

Makes it easier to recognise longs dumps.

Obligatory screenshot using "rx" prefix:

ath6kl: ath6kl_rx
rx 00000000: 10 10 00 00 00 00 08 30 00 00 00 00 00 00 f9 0b  .......0........
rx 00000010: 2c 44 08 30 00 00 f9 0b 0c a4 02 00 00 00 73 d2  ,D.0..........s.
rx 00000020: 94 00 f9 0b 04 8c 01 00 02 00 07 02 02 00 f9 0b  ................

Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
diff --git a/drivers/net/wireless/ath/ath6kl/debug.h b/drivers/net/wireless/ath/ath6kl/debug.h
index 91f4bc3..9f906c2 100644
--- a/drivers/net/wireless/ath/ath6kl/debug.h
+++ b/drivers/net/wireless/ath/ath6kl/debug.h
@@ -69,12 +69,14 @@
 	 })
 
 static inline void ath6kl_dbg_dump(enum ATH6K_DEBUG_MASK mask,
-				   const char *msg, const void *buf,
-				   size_t len)
+				   const char *msg, const char *prefix,
+				   const void *buf, size_t len)
 {
 	if (debug_mask & mask) {
-		ath6kl_dbg(mask, "%s\n", msg);
-		print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, buf, len);
+		if (msg)
+			ath6kl_dbg(mask, "%s\n", msg);
+
+		print_hex_dump_bytes(prefix, DUMP_PREFIX_OFFSET, buf, len);
 	}
 }
 
@@ -95,8 +97,8 @@
 }
 
 static inline void ath6kl_dbg_dump(enum ATH6K_DEBUG_MASK mask,
-				   const char *msg, const void *buf,
-				   size_t len)
+				   const char *msg, const char *prefix,
+				   const void *buf, size_t len)
 {
 }