core: Add a stat to track chaining frags

Keep count of single fragments and other fragment counts in increments
of 6 upto the maximum possible 16.

CRs-Fixed: 2992022
Change-Id: I1b1c474e51cf1fe8856d53511ae7c374caa0b4a2
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>

core/rmnet_config.h

@@ -61,6 +61,8 @@ struct rmnet_port_priv_stats {
 	u64 dl_trl_count;
 	struct rmnet_agg_stats agg;
 	u64 dl_chain_stat[7];
+	u64 dl_frag_stat_1;
+	u64 dl_frag_stat[5];
 };
 
 struct rmnet_egress_agg_params {