qcacld-3.0: disa: Replace explicit comparison to NULL

Per the Linux Kernel coding style, as enforced by the kernel
checkpatch script, pointers should not be explicitly compared to
NULL. Therefore within disa replace any such comparisons with logical
operations performed on the pointer itself.

Change-Id: Id25e4748819d206e361a55532a5ccfd648744b15
CRs-Fixed: 2418403

components/disa/core/src/wlan_disa_main.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2018-2019 The Linux Foundation. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for
  * any purpose with or without fee is hereby granted, provided that the
@@ -29,7 +29,7 @@ static struct wlan_disa_ctx *gp_disa_ctx;
 QDF_STATUS disa_allocate_ctx(void)
 {
 	/* If it is already created, ignore */
-	if (gp_disa_ctx != NULL) {
+	if (gp_disa_ctx) {
 		disa_debug("already allocated disa_ctx");
 		return QDF_STATUS_SUCCESS;
 	}

components/disa/dispatcher/src/wlan_disa_obj_mgmt_api.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2018-2019 The Linux Foundation. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for
  * any purpose with or without fee is hereby granted, provided that the
@@ -128,7 +128,7 @@ QDF_STATUS disa_psoc_object_created_notification(
 	DISA_ENTER();
 
 	disa_priv = qdf_mem_malloc(sizeof(*disa_priv));
-	if (disa_priv == NULL) {
+	if (!disa_priv) {
 		disa_err("Failed to allocate disa_priv");
 		status = QDF_STATUS_E_NOMEM;
 		goto out;