[qca-nss-drv] fix crash while reading ppe stats

Changes to move declaration of ppe pvt context into c file,
this was initially declared in .h file. With some recent changes,
same file is included into multiple c file which is causing an
invalid memory access while reading ppe stats.

Change-Id: Ic38bc162e94c79565e00c76ba5ae15cd2361f261
Signed-off-by: Amit Gupta <amitgupt@codeaurora.org>
diff --git a/nss_ppe.c b/nss_ppe.c
index b81c454..a914880 100644
--- a/nss_ppe.c
+++ b/nss_ppe.c
@@ -17,7 +17,10 @@
 #include "nss_ppe.h"
 #include "nss_ppe_stats.h"
 
+DEFINE_SPINLOCK(nss_ppe_stats_lock);
+
 struct nss_ppe_stats_debug nss_ppe_debug_stats;
+struct nss_ppe_pvt ppe_pvt;
 
 /*
  * nss_ppe_verify_ifnum()