qcacld-3.0: Replace DEBUG macro with WLAN_DEBUG

This is a qcacld-2.0 to qcacld-3.0 propagation.

pr_debug() should not appear by default in kernel log (kmsg).
DEBUG is a kernel macro, since host driver is using the same name macro,
pr_debug log statements are appearing in kmsg.

Fix this by moving the code under DEBUG to WLAN_DEBUG and
remove DEBUG macro from Kbuild.

Change-Id: I5bb385f91f9b6ba15629a5878625fefc21d4a7e1
CRs-Fixed: 1003261
diff --git a/uapi/linux/debug_linux.h b/uapi/linux/debug_linux.h
index 57c3590..428c90b 100644
--- a/uapi/linux/debug_linux.h
+++ b/uapi/linux/debug_linux.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2015 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2013-2016 The Linux Foundation. All rights reserved.
  *
  * Previously licensed under the ISC license by Qualcomm Atheros, Inc.
  *
@@ -31,7 +31,7 @@
 /* macro to remove parens */
 #define ATH_PRINTX_ARG(arg ...) arg
 
-#ifdef DEBUG
+#ifdef WLAN_DEBUG
 /* NOTE: the AR_DEBUG_PRINTF macro is defined here to handle special handling of variable arg macros
  * which may be compiler dependent. */
 #define AR_DEBUG_PRINTF(mask, args) do {	\