ath10k: Add wrapper function to ath10k debug

ath10k_dbg() is called in ath10k_process_rx() with huge set of arguments
which is causing CPU overhead even when debug_mask is not set.
Good improvement was observed in the receive side performance when call
to ath10k_dbg() is avoided in the RX path.

Since currently all debug messages are sent via tracing infrastructure,
we cannot entirely avoid calling ath10k_dbg. Therefore, call to
ath10k_dbg() is made conditional based on tracing config in the driver.

Trasmit performance remains unchanged with this patch; below are some
experimental results with this patch and tracing disabled.

mesh mode:

		w/o this patch          with this patch
Traffic       TP      CPU Usage      TP      CPU usage

TCP          840Mbps    76.53%      960Mbps    78.14%
UDP          1030Mbps   74.58%      1132Mbps   74.31%

Infra mode:

		w/o this patch          with this patch
Traffic        TP      CPU Usage      TP      CPU usage

TCP Rx       1241Mbps   80.89%      1270Mbps   73.50%
UDP Rx       1433Mbps   81.77%      1472Mbps   72.80%

Tested platform	: IPQ8064
hardware used	: QCA9984
firmware ver	: ver 10.4-3.5.3-00057

Signed-off-by: Kan Yan <kyan@chromium.org>
Signed-off-by: Venkateswara Naralasetty <vnaralas@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ath/ath10k/debug.c

@@ -2664,8 +2664,8 @@ void ath10k_debug_unregister(struct ath10k *ar)
 #endif /* CONFIG_ATH10K_DEBUGFS */
 
 #ifdef CONFIG_ATH10K_DEBUG
-void ath10k_dbg(struct ath10k *ar, enum ath10k_debug_mask mask,
-		const char *fmt, ...)
+void __ath10k_dbg(struct ath10k *ar, enum ath10k_debug_mask mask,
+		  const char *fmt, ...)
 {
 	struct va_format vaf;
 	va_list args;
@@ -2682,7 +2682,7 @@ void ath10k_dbg(struct ath10k *ar, enum ath10k_debug_mask mask,
 
 	va_end(args);
 }
-EXPORT_SYMBOL(ath10k_dbg);
+EXPORT_SYMBOL(__ath10k_dbg);
 
 void ath10k_dbg_dump(struct ath10k *ar,
 		     enum ath10k_debug_mask mask,
@@ -2695,7 +2695,7 @@ void ath10k_dbg_dump(struct ath10k *ar,
 
 	if (ath10k_debug_mask & mask) {
 		if (msg)
-			ath10k_dbg(ar, mask, "%s\n", msg);
+			__ath10k_dbg(ar, mask, "%s\n", msg);
 
 		for (ptr = buf; (ptr - buf) < len; ptr += 16) {
 			linebuflen = 0;