[qca-nss-ecm] Added -Werror flag to Makefile

Change-Id: I2f7ded23873bb5670a0c1da42fbfa0a7304d93a4
Signed-off-by: Gaurao Chaudhari <gaurchau@codeaurora.org>
diff --git a/Makefile b/Makefile
index 8051021..99bc5a5 100644
--- a/Makefile
+++ b/Makefile
@@ -353,5 +353,6 @@
 ccflags-y += -DECM_OPENWRT_SUPPORT=1
 
 ccflags-y += -I$(obj)/ -I$(obj)/ecm_db -I$(obj)/frontends/include -I$(obj)/frontends/nss -I$(obj)/frontends/sfe -I$(obj)/exports
+ccflags-y += -Werror
 
 obj ?= .