Platform: Rename NV counter enumerators

Rename the enumerators of the tfm_nv_counter_t enumeration to
eliminate any names related to other modules of TF-M.

Change-Id: I2cc1435c74ea1c27c72264a5f0b1fd8abab7dba2
Signed-off-by: David Vincze <david.vincze@arm.com>
diff --git a/platform/include/tfm_plat_nv_counters.h b/platform/include/tfm_plat_nv_counters.h
index c987ed7..26e213b 100644
--- a/platform/include/tfm_plat_nv_counters.h
+++ b/platform/include/tfm_plat_nv_counters.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, Arm Limited. All rights reserved.
+ * Copyright (c) 2018-2019, Arm Limited. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  *
@@ -19,9 +19,9 @@
 #include "tfm_plat_defs.h"
 
 enum tfm_nv_counter_t {
-    TFM_SST_NV_COUNTER_1 = 0,
-    TFM_SST_NV_COUNTER_2,
-    TFM_SST_NV_COUNTER_3,
+    PLAT_NV_COUNTER_0 = 0,  /* Used by SST service */
+    PLAT_NV_COUNTER_1,      /* Used by SST service */
+    PLAT_NV_COUNTER_2,      /* Used by SST service */
 };
 
 #ifdef __cplusplus