qcacmn: Use IS_ENABLED for the definition of kernel module

Add code to use IS_ENABLED for CONFIG_WCNSS_MEM_PRE_ALLOC
kernel modules and remove inclusion of reduntant header
file cnss.h.

Change-Id: If1d098c7c6f326d12700f06318909a7fc0e7895a
CRs-fixed: 2702368

qdf/linux/src/i_qdf_time.h

@@ -36,9 +36,6 @@
 #ifdef MSM_PLATFORM
 #include <asm/arch_timer.h>
 #endif
-#ifdef CONFIG_CNSS
-#include <net/cnss.h>
-#endif
 
 typedef unsigned long __qdf_time_t;
 typedef ktime_t  __qdf_ktime_t;

qdf/linux/src/qdf_mem.c

@@ -36,11 +36,7 @@
 #include <linux/string.h>
 #include <qdf_list.h>
 
-#if defined(CONFIG_CNSS)
-#include <net/cnss.h>
-#endif
-
-#ifdef CONFIG_WCNSS_MEM_PRE_ALLOC
+#if IS_ENABLED(CONFIG_WCNSS_MEM_PRE_ALLOC)
 #include <net/cnss_prealloc.h>
 #endif
 
@@ -1037,7 +1033,7 @@ void __qdf_mempool_free(qdf_device_t osdev, __qdf_mempool_t pool, void *buf)
 }
 qdf_export_symbol(__qdf_mempool_free);
 
-#ifdef CONFIG_WCNSS_MEM_PRE_ALLOC
+#if IS_ENABLED(CONFIG_WCNSS_MEM_PRE_ALLOC)
 /**
  * qdf_mem_prealloc_get() - conditionally pre-allocate memory
  * @size: the number of bytes to allocate